Only the expenses related to the rental portion can be written off.Allocation can be based on the square footage of the rental area relative to the total square footage of the house.As for your deductible expenses, you will need to allocate the expenses between the personal and rental portions of the house.

Assuming the sale nets $250K, does that mean the rental portion of the multi-family property will need to be valued above $250K using square-footage?  

I am able to do a CMA (Comparative Market Analysis) for you with specifics based on what you are looking for, however- I just need square footage, zip code, number of bedrooms and bathrooms, neighborhood, year built and age of home/upgrades and improvements to compare.

The square footage is applied to the main house as well.

Computers can calculate square footage, number of beds/baths, and other objective criteria, but they can't measure the subjective things like curb appeal, flow of the floorplan, view out the living room window, or the grating irritation of four barking dogs in the neighbor's back yard.Learn to study the market and how to evaluate properties on your own.

Section 8 may call it a BR if it is over a certain Sq Footage and has a closet and then your approved rents go up. 

Hey Donna,Verify bed/bath count and square footage with the other rental listings that appear, but the median rent should provide a rough estimate of rent per unit.

May also want to maximize square-footage of property in comparison to land size, since land does not contribute to costseg3. costseg/STR: after one year, convert the entire building to AirBnB rentals4.

I should also mention that properties with an ocean view in my condominium have sold between $1.2m-1.3m but also have less square footage and less bedrooms and bathrooms.

You have to find properties that have dens, additions, larger square footage to find rooms.