For the 15-year issue: "Building" as in the Real Estate on some property? Or, "building Out" as in, improving the real property they are leasing? See:

https://www.jccscpa.com/bar-restaurant-industry-irs-depreciation-changes/

For some details. You want to separate "cost" as Expense, and Cost as invested in the asset. And, group assets for same Type. Lawyers and Fryers are not the same asset. And the lawyer was for the entity or the business? Utilities are operating costs, and "materials" can be lots of cheap stuff that won't last very long, or a few expense things that will last a while. That means understanding Asset vs Expense and Safe Harbor rules.