They put one of their employees into one of my houses, and after I switched to a new property manager, that tenant stopped paying rent (amazing!)  

This is my third year investing with my mini me 12 year old and this is our 5th deal.My 12 year old found us a great deal- I teamed up with my friend and family member agreed to pay purchase and renovations.

Personally, If I could pull out a HELOC, I would use it to fix and flip which will typically make sense as you shouldnt be keeping the money out for that long and you can recycle it or pay it back and build off the capital that you got from. the flip.

Most 401ks give you 30 or 60 days to pay back a 401k loan or they count it as a withdraw and that is a taxable event. 

To confirm, did they pay timely and what kind of condition the property was left in. 

We explained to him we would pay for probate and pay to fix up the house to get it rented.The lease is for 5 years but dissolves once we close.

Now, you need to figure out how to find deals and pay for them.

Doing this will indefinitely defer paying tax on profit or depreciation recapture. 

Or just pay your sister a finders fee for getting the deal?

If the tenant is claiming to be living in a hotel, she may try to get you to reimburse for that cost unless section 8 has a new process to reimburse them for this... which sounds absurd but I'll let you deduce whether or not you're dealing with someone who is used to paying for things out of their own pocket.