About We also specialize in renovation projects for existing old buildings. This involves demolition planning, applying for demolition permits, signing agreements with adjacent property owners, structural engineer assessments, renovation permit applications, contractor selection, exterior design plans, completion permit applications, and the finalization of interior renovation designs. In the case of older buildings, extensive demolition is often required, and everything removed needs replacement or refurbishment. This can sometimes result in costs exceeding twice the estimate for new construction. For larger properties, costs may even approach those associated with luxury real estate. Regarding overall construction costs, we suggest aiming for a range of 50% of the property value, which is considered a reasonable guideline.