The 5 percent you pay an agent to properly market a nice property will far outgain what you will lose involving someone who will come in and pretend they have the money to buy just to daisy chain it to every Facebook group in the area.

I also use PayPal and Venmo.Some just deposit directly into my business account.I make it as easy as possible for my tenants to pay me.

Actually now if someone can pay me to do it, I would do it by now LOL .... this is way more profitable than chasing CF. 

Are there additional taxes to pay? 

I offer either 10% monthly and manage everything including accepting rent and paying owners, or on call management. 

Tenants pay for utilities, so for expenses I have vacancy 8% ($198), taxes $395, insurance $85, maintenance 3% ($74), CapX 5% ($124). 

(Just to get back to even with selling today.)If your payment becomes $3500 and you collect $5,000 in rent with no PM charges, and everyone pays on time, and nothing breaks.

The tenant is expected to notify you, and maybe they will, maybe they won't.Because they have nowhere else to go and no funds (and usually no job),  you'll be paying for an eviction. 

Hi all, I'm looking at some single family properties in the area and there is one for sale that says the current tenants are paying $500 below market value.

You can call it 'overpriced' but others are willing to pay it, so I'd focus on finding the best deal you can find in your area, and not on a CoC return rate that may not be realistic these days.