If you've got a luxury STR (say, ski-in ski-out cabin in Vail or beachfront villa in Barbados) I think you have the most to worry about - it's expensive to travel there (usually by plane), expensive activities (like skiing), just all-around expensive.  

When the weather is nice, usually spring and summer.  

They don't give the phone number but if you Google the person and hunt around you can usually come up with a number.   

NNN leases are usually commercial properties that have 20-25 year guaranteed leases, that the tenant (franchise) pays for everything except you buying the building. 

If I use my normal title company they will check for liens, verify taxes, etc as per usual before closing, correct?

That is usually the rule of thumb.

I usually go to google and type my search with "biggerpockets" after and get much better results. 

The properties that have their yards in bad shape and the houses look like they need work are usually the ones you should stay away from. 

It is usually well worth it to buy the list.

DOT's usually have certain road frontage rights for road widening.