Pay attention to @Sylvia B.Also, borrow on credit card but make it habitable and enjoyable by any tenant you choose. 

If they do, I wouldn't pull the "trust" card out as they will roll their eyes when they accelerate the note.

Our total debt with student loans and credit cards is around $315,000.

I secured a personal loan for labor costs and a Home Depot credit card for material purchases.

Monthly expense is $388 (repairs, vacancy 7%, misc, management fee)This leaves a cash flow of $912 There is no mortgage but I have credit card debt which has negatively affected my credit I have a cash out for 87k (net)mortgage at 9% estimate.

Has a credit card, but never used it, paid everything cash.

We are not taking on any personal debt to pursue this journey; we don't have car loans, student loans, or carry credit card balances. 

(I’m aware of the strategies I’ll be taking in terms of increasing credit score through small credit card payments etc)For example, I live in NYC, a market that is infamous for being high-barrier entry, so I would mostly be looking at rental properties in the New Jersey area.

Using credit cards might be the way to go.

My concern with rent collection service is potential chargeback, specially if it's paid by credit card.