Thanks for reaching out! The answer to that is largely a question of the region in which you plan to build. For example, this house was built in Napa Valley, and with labor costs being higher The addition and remodel costs were probably as high as $700 a square foot.

We have worked with builders in places like North Carolina or Utah where it’s probably 20 to 30% less than that.

However, cost factored by square footage are very risky because it can be unclear, what’s included and excluded.

Driveways, pool and Hardscape, Landscape, utilities, are all things that should be included, but often or not

This is a much longer conversation that I think you could have with local builders in your region