People have done loans subject to but the original borrower stays on the loan and it could be at risk to be called once a deed is transferred

Hostaway is not the cheapest software out there, but it has the most stable connections, reliability and 24/7 support. 

These are reputable people who stand behind the properties they find and are reliable for ensuring a smooth transaction.

The property manager should transfer those funds to you.

Having the right attorney is a big part of the business, but also understanding how violations, town inspections, zoning certs, transfer stamps, PTAX and other "fun" parts of the closing process work are a huge part of what we do as agents. 

I no longer get tech support/updates, but the software does what I need it to do pretty reliably.

This means that I don't need to transfer random amounts of money to another account to pay a mortgage because the tenant on that property is late paying this month or other nonsense like that.

I would include at least the heavy hitters like title insurance, transfer taxes, appraisal, and paying my closing agent.

Being out of state, you will want an agent who has good relationships with reliable inspectors, title companies, contractors, property managers, lenders, wholesalers, insurance agents, other RE agents, etc.

You should consider: appreciation, can you get reliable property management there, crime area, etc to name a few.