A modern desert house with a pool and horse
Who we are


Honor the past, challenge the norm, and inspire the future.

Our name

We are often asked how we came up with our company name, The Ranch Mine. Before we formed our company back in 2010, we spent 7 months traveling around Arizona, exploring the history of our state. During these trips, a common thread started to emerge: the pioneer spirit. Everywhere we went we heard stories and saw manifestations of the driven, impassioned people, such as ranchers and miners, who were willing to endure hardship in search of a better life. This spirit is still alive and well today in many of you, the modern pioneers, and serves as inspiration to continue journeying into the unknown to craft original and diverse living experiences.

Our story

In 2009, Cavin Costello received his Master of Architecture degree and made the drive to Phoenix, Arizona sight unseen, inspired by the complexities and opportunities to be had in the American Southwest. He had not yet been a full day in Phoenix when he met Claire, a Phoenix native looking to make the most of her recent move back home. The two quickly bonded over their ideals of the built environment, how to improve upon it and its ability to influence. Not settling for a hard hit economy to dictate their next move, the duo decided to act. So, they bought a fixer upper and experienced first hand the trials and tribulations of a major renovation.

The two continued paving their own path developing the First Phoenix Green Construction Code project, designing for visionary real estate developers, and creating unique homes for trailblazing homeowners. Cavin and Claire have continued to push the envelope in designing for modern pioneers which has won them 6 national awards including the HGTV Designer of the Year contest in 2019 and 2023, a 2015 National American Institute of Architects contest that named them the “Future of Architecture”, landed them features on the NBC Today Show and with HGTV, and had their work published in numerous books and publications on 6 continents around the world.

Our mission

We exist to help connect you with nature, encourage curiosity and exploration, and enable you to do more of what you love.

Our team

Behind every project we take on is a highly-skilled team. Following suit, our team is composed of adventurers who each possess the pioneer spirit and strive to break the boundaries of conventional thinking.

Cavin and Claire Costello

Cavin Costello

Principal Architect

Cavin Costello is the son of a civil engineer who endeavored to build his own house in rural Connecticut. It is safe to say that this exposure to building systems mixed with a “go get ’em” attitude laid the foundation for Cavin’s future. Cavin pursued his childhood passion at Northeastern University from which he earned a Bachelor of Science in Architecture and a Master of Architecture degree, graduating Summa Cum Laude. During school breaks Cavin used his free time to explore, traveling the country visiting numerous cities, states, national parks, and historical sites, building his appreciation for nature and history and learning how culture and context affect the built environment. His enthusiasm for adventure led him to Phoenix, Arizona where he has become a prominent figure in the community. To date, Cavin has designed over 200 projects around the world, winning multiple national and local awards, including HGTV’s “Designer of the Year” in 2019 and 2023 and “The Future of Architecture” award from the American Institute of Architects in 2015. Cavin is a licensed Architect in Arizona, Tennessee, Montana, Colorado, Texas and North Carolina.

Claire Costello

Chief Executive

Claire Costello is a native Phoenician who received unique exposure to rambling ranches, mid-century modern and desert architecture. Claire was young when she was asked to pick up a shovel and do some dirty work at her aunt and uncles in Tucson. This “dirty work” was digging dirt to build the first rammed earth house Claire had ever known of. Leaving the desert behind, Claire ventured to the University of Colorado at Boulder where she received concurrent Bachelor of Science degrees in English and Communication. Her time away from Arizona led Claire to travel the world, fueling a desire to make real change and igniting a belief in the power of action. Upon returning to her hometown, Claire sought to make a familiar place new, exciting and her own. Emboldened with an entrepreneurial spirit, Claire is committed to improving her hometown of Phoenix one home at a time. Today, Claire embraces a hands-on approach to design and development and works toward shaping a more vibrant community.

Rachel Connor Karle

Project Architect
Rachel Connor Karle

Growing up in Arizona, Rachel developed a robust appreciation for the joys and challenges of desert-dwelling. After years of traveling to different states and countries, learning from various cultures and people, she returned to Phoenix in order to employ that knowledge while engaging with the built environment. This, in addition to her background in both architecture and engineering, has allowed Rachel to approach design with a unique perspective that she continues to develop and apply to every aspect of a project.

Rachel joined The Ranch Mine in 2018 shortly after receiving her Masters of Architecture from UCLA. She also earned her bachelor’s degree in Structural Engineering from Brown University. She is a registered architect in the state of Arizona.

Geoff Sosebee

Senior Designer
Geoff Sosebee

Geoff grew up in Georgia during a time when houses were being built by the hundreds. Walking through those neighborhoods during construction is when he fell in love with Architecture. It was also during this time that he was first introduced to the desert southwest during a backpacking trip to New Mexico.

After undergrad and living in Europe, Geoff moved to Oregon for graduate school for a change of pace and scenery. It's here that his passion for mountain biking, trail building, and architecture began to really formulate. He spent a number of years working on projects of all scales and typologies including; digital fabrication, creative office renovations, performing arts centers, multi-family residential, and various mass timber projects. During this time with Lever Architecture, he was able to focus on his original love of residential architecture, working on a number of residential projects over a few years.

In an attempt to escape the pacific northwest winter, he found himself in Phoenix for a sunny vacation and it's there that his childhood memories of the desert southwest resurfaced and he knew he needed to find his way back there professionally.

Geoff holds a BS in Architecture from Georgia Tech and a MArch from The University of Oregon.

Nicole Mehaffey

Project Architect
Nicole Mehaffey

Nicole was raised in Southern Louisiana where art classes, folders of unbuilt treehouse designs and a deep curiosity for the region's unique blend of culture, architecture, music, and cuisine were her gateways into the creative world. Hurricane Katrina expanded her understanding of the boundless powers of nature over the built environment, influencing her choice to pursue an architectural education.

After graduating with a combination BS and MArch from Tulane University, she sought out a new and entirely different locale by moving to Phoenix. She spent over 6 years working in commercial architecture on a varied collection of project types and scales, including multifamily residential, municipal, master planning, adaptive reuse, and behavioral health care.

Nicole enjoys reading, cooking, and exploring, and has gotten to know the desert intimately through camping, offroading, hiking, and paddleboarding. She joined The Ranch Mine in 2022 and is a registered architect in the state of Arizona.

Benjamin Johnson

Visualization Specialist
Benjamin Johnson

Benjamin was born and raised in the United Kingdom, where he earned a Bachelor of Architecture at the University of Lincoln. Ben went on to work with a variety of successful architects in the UK whilst continuing further studies in architecture. His love of travel ultimately led him to the United States and a move to Arizona in 2015.

Having gained a wide experience in high end residential and commercial projects, both in the US and Europe, his passion for exceptional design continued him on a path to The Ranch Mine in October 2018. Specializing in 3D visualization and representation he became an integral part of any project.

Katie O'Connell

Project Architect
Katie O'Connell

Growing up in Tennessee, Katie developed a love for varying landscapes from the plains along the Mississippi to the old forested mountains of the Smokies. This gradually evolved into a passion for experiencing different cultures of the world, understood through not only the landscape of the place, but also the food, architecture, and people. After working in London and New York, she decided to return to the mountains, this time in a valley surrounded by giant Doug Fir forests and old sleeping volcanoes - Portland, Oregon.

Katie has ten years of experience in creative office, hospitality, mass timber structures, and high end residential. Her passion lies in the latter, where architecture becomes most personal and tactile. Katie’s focus on exceptional design lends to architecture that is of a place while also deeply personal and reflective of the clients she works alongside.

Katie joined the Ranch Mine in 2023. She holds a Bachelor of Architecture from the University of Tennessee and is a licensed architect in the state of New York.

Blake Preszler

Senior Designer
Blake Preszler

Born and raised in the vast prairie landscapes of North Dakota, Blake discovered his passion for architecture and design at an early age. It all began within the walls of a mid-century split-level house—the very place where his creative spirit took root.

As a child, family road trips to Montana ignited a love with the rugged beauty of the Rocky Mountain West. These adventures shaped his perspective and set him on a path toward higher education at Montana State University. After earning a Bachelor of Environmental Design and a Master of Architecture degree, life's twists and turns led Blake back to North Dakota. There, he honed their skills by contributing to diverse projects—ranging from residential to commercial and institutional. The mountains kept calling, and Blake eventually found his way back to Montana where he worked as the in-house designer for a local development group.

Blake enjoys going on adventures with his family, mountain biking, and catching a good sunset. With over 15 years of experience, Blake joined The Ranch Mine in early 2024.

Shelby Taubenkimel

Project Architect
Shelby Taubenkimel

Shelby is originally from South Florida, where she danced competitively and had a love for arts and crafts, both of which she credits for sparking her interest in design as a whole. Her passion for architecture specifically grew as she completed her Bachelor of Design at the University of Florida and went on to receive her Master of Architecture from the University of Texas at Austin. She worked as a Teaching Assistant for theoretical courses such as Architecture and Society and Creative Problem Solving, and was involved in the Gulf Coast Design Lab, a design-build studio focused on environmental activism.

Upon graduating, Shelby decided to keep calling Austin home, inspired by the opportunity to continue exploring the Texas Hill Country landscape and ever-changing city. Shelby holds a deep belief that architecture and design should play a positive role in the world around us by elevating everyday experiences, which drove her to the world of custom residential architecture.

After years of working on high end residential and boutique commercial architecture in the Austin area, Shelby joined The Ranch Mine in early 2024. She is a licensed architect in the state of Texas.

National and International Awards & Honors


Designer of the Year – Countryside Escapes, People’s Choice Winner, HGTV – 2023
Best Single Family Detached Home 3000 to 3,499 SF,
Gold Nugget Awards – 2023
Best Project, Archilovers – 2020, 2022, 2023
Top Home Tastemaker on Contemporary Design, Artful Living Magazine – 2022
Top 10 Sustainable Homes of 2020 – #3,
Dwell Magazine – 2020
Designer of the Year – Before + After, Editors’ Choice Winner, HGTV – 2019
Designer of the Year – Before + After, People’s Choice Winner, HGTV – 2019
10 Talented Architects Leading the Way with Site-specific Designs that Engage with Nature, Luxe Magazine – 2018
Top 10 US Houses of 2017, Dezeen – 2017
Top 20 Homes of 2017 – #12, Dwell Magazine – 2017
2017 Building of the Year Finalist (United States), American-Architects – 2017
The Future of Architecture: Innovation, Winner, American Institute of Architects (AIA) and Houzz – 2015
Designer of the Week, HGTV – 2015
Green Remodel of the Year: National Award-Winner, National Association of Home Builders – 2012
Best Homes Across the Country under $250,000, NBC Today Show – 2012

Local Awards & Honors


Best Modern Architect to Watch - Modern Luxury Scottsdale - 2024
Best Sustainable Architect or Architecture Firm - Best of Arizona -
Green Living Magazine– 2023
Best Modern Future Home -
Modern Luxury Scottsdale – 2023
Best Mid-Century Modern Home Design Firm - Southwest USA –
Build Magazine– 2023
Home of the Year –
Home Builders Association of Central Arizona – 2022
Best Architectural Design: Homes From $800,000 - $1,000,000 – Home Builders Association of Central Arizona – 2022
Design Icon – Architect,
Sources for Design Magazine – 2021
Gold List, Luxe Magazine – 2020, 2021, 2023, 2024
40 under 40 Inaugural Class, Phoenix Magazine – 2018
Best of Houzz: Design, Houzz – 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023
Big Brain Award Finalist: Design, Phoenix New Times – 2015
35 top Entrepreneurs under 35 , The Arizona Republic – 2013
Best Emerging Creative Duo, Phoenix New Times – 2013
Top 100 Creatives, Phoenix New Times – 2012

Where we've worked so far:


While our firm is based in Arizona, we work for people with the pioneer spirit around the world. Below is the list of the places where we have worked so far. Get in touch to see if we'll work in your area!

North Carolina

El Salvador

Our work


looking through a pivot door to a boat house on a lake
Reach out