Since these homeowners are potentially sensitive about the subject of foreclosure, are their some things I should avoid asking over the phone? 

Additionally, I had a fire in one upper and that produced water damage in the lower, THEN kicked in the teeth with a move-out - - ALL in the same month. 

BUT you have to be sensitive about appraisals.

There is a rehabber here that bought a house with about 60K worth of retaining wall that was unpermitted, he thought he could permit it no problem then found out because it was a biologically sensitive area he couldn't permit and also was going to have to spend about 75K to remove the walls and re-establish the habitat to the pre-wall condition .

That fee, hopefully, is really about having teeth behind your rent due date, not about making extra money.

One that is extremely conservative in their underwriting, purchases below market and is very thorough with their sensitivity analysis.

This is time sensitive because I'm in contract with a buyer.

., making me uncomfortable when it comes to working on something so time-sensitive as a rehab.

Some investments are highly sensitive to market factors (high beta) and some are not.

This is an extremely inefficient and outdated pulling teeth to do business.