One option is to "charge them" rent for the new sq ft at market rates.  

Third Largest City in Alabama with an unemployment rate of 3.5%.

However, I've personally stopped taking Section 8 tenants because they ultimately resulted in lower rent income, a higher rate of lease violations and problems, and increased costs at turnover.It also depends on your market.

Bigger Pockets is a great place for education and networking and is full of great content.I recommend that you check out the following resources:1.

What made you interested in investing in this type of deal?

Sell 1/2 interest to a partner at a profit to yourself.

After a good stretch in real estate, I’ve found that the best deals often come from great conversations.

Great Information Mike thanks.

The great ones stand out. 

Section 8 tenants can be great, but the properties do have to meet specific housing standards, so factor in potential renovation costs to ensure compliance.