(Not a lawyer so this is not legal advice) You've listed all the reasons why people fire property managers, it sounds like they've just done a poor job of meeting your expectations. 

We have rented the long term unit to family friends for over a year and the bills were always reasonable.

So far no deals I have found are even close to creating reasonable if any cash flow with 20% down.

A reasonably good source is AVVO.com by zip code and expertise.  

While we are not tax professionals ourselves, we do share how we ourselves have made millions and paid very little taxes along the wayAlso @Eli Edwards A network of relocation specialists is not a reason to invest in a course.  

The reason so many people struggle with wholesaling is simple: they don’t understand lead generation.Take a moment to think about your approach.

Part of the reason we have that equity in our homes is to tap into it and turn it into even more wealth.

Analyze the WHY behind your current investors reasoning for not partnering up with you.

You could also get a line of credit for about $150k (you should be able to borrow 75% of the value.)The reason I suggest this is…1) you save $40-$60k in selling costs. 2) you have a lower blended interest rate (2/3rds at 3.25% and 1/3rd at 7 or 8% instead of the whole $500k at 7 or 8%) saving you another $1k/mo in interest. 3) you only pay interest on that $150k when you actually use it, not from day 1  Unless you hate this property, or want to buy something you can’t afford without selling, that would be my plan.

I imagine a lot of the reasons will overlap with the previous topic.