Whether bank or credit union - either will work. 

The program was created to give low-income tenants an alternative to living in federal project housing.S8 sets their rental rates to the LOW-END of market averages, if not slightly below.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

Anyone that is looking at your assets is always going to need to factor in property management, so you can show that as a real expense (and really make it as high or low as you want).I work in a vertically integrated real estate and development company, and I cannot imagine how things would run if we did not have an internal property management company that essentially works for the other companies but also stands on its own.

Looking for a house we could house hack, had an incredibly low interest rate on mortgage and house has increased in value about 42%, an estimated 180k in equity.

But I'm guessing maybe your credit is too low for that?  

It simplifies the process since Zillow handles credit, income, and background checks for a small fee paid by the applicant.Background Check Services: If you prefer not to use Zillow, consider using services like MySmartMove or RentSpree.

Fico while they will look these are not credit score driven loans like those buying rental houses or houses to live in...

It's highly unlikely to go that low again in your lifetime.

I’ve been a serial house hacker in the greater Boston area so happy to connect and share some lessons learned.Multifams inventories are quite low depending on your budget and location preferences.