I don't know Waco economics at all, but I'll bet there are 1000 units of some kind available for rent a town of 140-150,000 seems like a lot to me. 

Just a short list its like 50 ways to leave your lover there are 50 gothcas in sub to. 1. the easiest for everyone to understand the sub to violated the Alienation clause in the mortgage or deed of trust and holder of the mortgage DT / Note decides to call the note due and payable and starts a foreclosure. 2. foreclosure started and the person who bought sub to has no means to pay it off or refinance it and the original sellers credit get trashed and if its a deficiency judgement state even on an owner occ like Texas lender sues original seller for the deficiency. 3. this kind of investing or acquiring assets tends to attract those with limited resources so they have no ability to fix things they decide to scale up and then it goes out of control and sellers are really harmed4. deal goes south and original seller sues or files complaint with AG. 5.

Does anyone have rule of thumb cost estimates for this kind of work?

Buildium's bank sync/feed is a hit or miss kind of situation.If you are using Buildium and can connect your bank accounts to it, then there is no need to get QBO subscription.

If they didn't respond kindly to sincere attempts to fix the problem, I'd mention your attempts.

This kind of plays into the booking issue many have alluded to here.

If I am about to search for some kind of cash out refinancing options, is it best to keep the properties in my personal name for now or should I move them into LLC’s before searching for financing options?

This is kind of implied in the other points, but talk to an attorney and know what legal exposure you might be looking at.

As you know, you can find all kinds of resources on BP. 

This wasn’t just me—this was true for most Florida property owners back then.But that kind of system can’t last forever.