I am an appraiser needing to establish market rent for a two-story, single tenant bank branch building with a full basement. It was leased to the current tenant 25 years ago with no rentable area specified; the lease defines the premises as the parcel along with all improvements on the parcel.
The windowless basement has a small finished break room, and the rest of the basement consists of a large (but walled-off) storage area in the center of the basement, wide corridors along the perimeter of the storage (the perimeter of the basement), and some mechanical and electrical areas on one end of the basement. The storage, corridors and mechanical/electrical areas have bare concrete floors, painted drywall ceilings with exposed conduit and HVAC ducts, painted drywall walls. Standard ceiling height.
The lease is coming up for a renewal, and I need to determine what square footage should be used in calculating monthly rent. Our local market suggests using different rental rates for the ground floor, second floor, and basement. My problem is that I am not sure how to handle the basement, more specifically the corridors, mechanical and electrical rooms. Should they all be counted in the rentable area of this single-tenant building? The corridors serve no useful purpose because they were created as a by-product of demising the storage, which the tenant is not using.
Your suggestions would be greatly appreciated!