These are mechanical things that can be done with a dose of common sense, made easy with some youtube video and online forums.

When I take my car to a mechanic, he provides all material and labor prior to my paying (days/weeks).

Don, I am a Contractor and Investor from Philly Suburbs..I would find out if all 3 guys are skilled mechanics or a mix of mechanics and laborers.

Most liens like mortgage or 'mechanic' liens (if the homeowner did not pay the roofing company), will effectively be wiped out by the tax deed sale.  

It's totally different from using a mechanical snake.

If not file a mechanic lien.  

Reasons are as follows:- House will be easier to resell in my area than older homes- After about 20 years, houses need a lot of cosmetic and mechanical renovation, including roof replacement, HVAC replacement, siding repair, new fixtures, new appliances, etc.

For a complete remodel I usually say 2k per bathroom labor and material.5) In indiana, if you are selling the home within 12 months you are not allowed to do any of the major work on mechanicals, and need to hire licensed profesionals which gets pretty pricey.

There are usually structural problems, broken pipes/massive mold, all major mechanicals need replaced as well as old windows and roofs.

If all the systems and mechanicals are old the repairs will eat up any expected returns for years if things go perfect with your tenants.The key question is if the previous owner did a lot of deferred maintenance and kept hoarding cash instead.The HOA doesn't mean anything.They can go defunct or increase the dues or add special assessments.I like to keep control of my investments so do not like deals like this where you are betting on an external party to maintain your property.