You’ve probably seen the ads: “Build your dream casita for $99,000!” or “Complete barndominium kits starting under $100K!” At first glance, buying a prefabricated building or kit online can seem like an affordable shortcut to adding living space to your property.

But before you click “Order Now,” it’s important to understand exactly what that advertised price includes—and, more importantly, what it doesn’t.

Many online prices cover primarily the structure or building package, leaving the homeowner responsible for significant expenses required to turn that package into a completed, permitted home. Depending on the product, additional costs may include site preparation and grading, excavation, foundations, utility connections, shipping and unloading, engineering, permits, assembly and construction labor.

And the expenses may not stop there.

Cabinets, countertops, flooring, plumbing fixtures, electrical fixtures, appliances, HVAC systems and other interior finishes may be additional. Your property could also require drainage improvements, septic modifications, utility trenching, driveway access or other site-specific work.

Suddenly, that attractive online price can look very different from the actual cost of a move-in-ready casita or barndominium.

That doesn’t necessarily mean prefab construction is a bad option. It means homeowners should understand the total project cost before purchasing a building package.

At Cornerstone Construction Services LLC, we encourage homeowners to talk with a knowledgeable local contractor before committing to an online kit. A local contractor can evaluate your property, discuss permitting and site requirements, identify costs that may not be included in the advertised price, and help you compare prefab construction with a custom-built option.

Sometimes the online kit still makes sense. Other times, you may discover that a traditionally built, custom casita designed specifically for your property provides greater flexibility and value.

Thinking about building a casita in Tucson or Pima County? Talk to us before you buy. We can help you understand the whole project—not just the price of the box.