Rental analysis for a property in Langley, Oklahoma

[Ashwin kumar Kovur]

I am looking at a property which used to be a motel in past, now converted to multifamily in Langley Oklahoma, close to Grand Lake Cherokee. It currently remodeled into 1 3bd/2ba, 3 1bd/1ba and 2 studios and 1 cabin, total 7 all at one place and fully remodeled and tenants in place priced at $550k.

Seller is willing to reduce the price to $485k, but county assessor fair cash value shows as $404k. Can we base our negotiation based off county fair cash value or is it just for property taxes. 

Also, any input in regards to how the rental market is in Langley area around Grand Lake Cherokee. Does it get busy during summer times, so that I can convert cabin to a short term rental.

Any help is appreciated!