Some will find hidden opportunities and thrive.

I currently drive for Lyft full time to learn the area, meet people, and find hidden deals.

Why haven't you already provided them with payment instructions?

If all their stuff is still in there, then there could be hidden things that I can't see.  

It needs a full gut remodel, but this seems very doable given that I would have around $120-140k to work with as a rehab budget (home is only 1600 sq ft).This project would be a bigger scope than the two flips I have done, so I am wondering, what are some of the hidden costs and challenges to doing a conversion like this?

I don't continue to follow up and ask what they intend to do because I already gave them the instructions with the notice.

Instructions are on the link to the Google Sheet provided on this hyperlink. 

Hidden costs.

I think it's hard for a tenant to know the difference sometimes between issues they can/should address themselves and something they should call the landlord for, especially when they've been instructed to handle small maintenance issues themselves (as you state) because you're out of town.He probably thought this was a small issue, tried to address it, then it became bigger. 

I can see a day when giving professional instruction will be a licensed matter in real estate, as it should be!