Most credit issues can be addressed in some way.

Credit Score: 

You have to put 5% down vs 3.5% down, rates are usually higher, but if you have strong credit, your PMI cost can be cheaper than that of FHA loans. 

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

I can buy a 2-4 unit with 20% down vs conventional can only buy a 2-4 INVESTMENT property with 25% down 4. there are options where DSCR loans dont repot to personal credit, helps in not having to show a bunch of paperwork or not one person in a partnership has to carry the debt5. way less paperwork to close on this loan type vs a conventional loan. we care about the income of the property you're buying and it's ability to service the debt of the property whether we use long term rents income, lease income, or air dna/bnb income.6. easily buy in partnerships, add people to your operating agreement, its as easy as that so bring partners into a deal. helps with scaling and raising capital or getting partners involved7. gift funds allowed to close on these as well, and like I said earlier, there's only a 10day seasoning period of funds with some lenders so that means you can literally have a private money lender deposit money into your account 11 days before closing, and you can use those funds to close!

Appraisals came back awesome my credit score came back 720.

Even more than credit, the more experience and capital you have, the more aggressive a lender is going to be.

The sub 550 credit score people come out of the woodwork to apply for this home. 

It's a tip I heard from someone which I heard increases the response rate. 

Credit?