If you go into A/B Class the rents are going to be too high to justify doing section 8, meaning market rents are higher than Section 8 is able to pay.If you go down to D Class areas you're going to attract terrible tenants and it will be a nightmare. 

So property rents must be kept near market to obtain full value at sale.

You may also want to check the Columbus OH market - great macroeconomics with lots of job and population growth along with major companies developing here that drive strong rental demand. 

Quote from @Jill Kirby: I just jumped in to the short-term rental market.

Look at their marketing strategy.

“Lyons, I love seeing someone with your drive and vision diving into multifamily real estate in LA—you’re in one of the most competitive and opportunity-rich markets out there.

Another option is to invest in the market instead of paying down a mortgage.

Do you have a specific market you are interested in? 

Most Brokers on this site work very specific markets.

You have fixed cost so it is better to get some bodies in there so you can get market rent later.