I think I heard on one of the BP podcasts that a good rule of thumb is to ensure there are at least 3 different types of major industry in a city. 

Property Management reserves the right to reject any application due to any one or a combination ofthe following:• False, incomplete or insufficient application information;• Credit score 550 or less,• Credit showing delinquent accounts with collection balances due; foreclosures, bankruptcies, liens againstthe applicant for taxes or child support, judgments against the applicant for evictions or property damage;• Rental histories showing excessive late payment, NSF checks, property damage, lease violations;• Income shortages less than the required monthly amount;• Criminal histories showing felonies, misdemeanors, DWIs, DUIs, theft by check, domestic violenceHaving something like this will help you eliminate "gut feeling" criteria and ensure you are treating all to the same standards of qualification. 

So, if you want to ensure that you have positive cash flow, you need to ensure that your monthly loan payment is less than this monthly NI amount.There are more complicated ways of determining whether you'll have positive cash flow (stemming from positive leverage) using the cap rate of the property and the loan constant for your loan, but the above is the easiest way to start.

Also I would see consider the numbers tenants in one side and only you on the other,  just to ensure you have the funds to back the risk.  

Let them know your strategy, your goals and what your business plan is to ensure that your business plan aligns with theirs and you can both work towards the same goal.

My advice would be to ensure that you have a good experience on your first transaction.

There is going to be an increased amount of paperwork Holton-Wise must perform on your behalf while working with CMHA.Holton-Wise will need to physically appear at CMHA's office multiple times.Holton-Wise will need to coordinate one or possibly more inspections at the rental property with CMHA's inspectors to ensure is is compliant with their regulations.If / when CMHA determines that the property has a violation that needs to be corrected to adhere to their standards Holton-Wise is given a very short window to correct it which means Holton-Wise must give you priority scheduling over all of Holton-Wise's other clients and Holton-Wise may even need to do this multiple times as sometimes tenant's exit the voucher program and or move onto something else while Holton-Wise is going through this inspection process with CMHA.It typically takes anywhere from 30 days to 60 days from the time Holton-Wise approves a tenant's rental application until the time that CMHA approves the rental property for tenancy on the Section 8 program.CMHA prohibits Holton-Wise from passing on some of your rental unit leasing costs to the tenants like Holton-Wise does with normal cash paying tenants.Q.

How to I ensure I get paid once I assign the contract .

What systems do they have in place to ensure you have transparency into your investments at all times?

As prior posters, mentioned you can file a judgment and the chance to collect maybe low, but the key is to secure your property and ensure no further damage is being done to it at the moment.