It’s common to run into unexpected problems that push your costs way above what you planned, which could turn your profitable flip into a financial headache.And don't forget about taxes!

I believe it is just common courtesy on top of me spending money to send out the letters.  

The tenant's mention of a lawsuit is typically an empty threat.As someone that's dealt with plenty of mold and mold claims, this one looks like a fat nothing burger.

Thanks Drew,Is it common to run into issues with the probate process?

Common complaints I hear is timeliness of communication, but it doesn't seem to be from everyone.

One common advice I have noticed is purchasing a duplex or multi family home in your area or at least 30 miles within proximity.

There is a common misconception about deleading cost and how it can be done.It varies from situation to situation, it could be as simply as covering hazardous element with some plywood or metal, or it could be some replacement doors/windows and making paint intact.

Here in TX the soil is mostly clay, and it shrinks and expands with humidity level (thus the need to "water the foundations" as a measure to avoid foundation cracking), so foundation problems are a common occurrence.

My biggest STR home run was purchasing a property in a vacation market before STRs were common.

Very rarely, those cases happen due to some fat tails event-- recession, war, pandemic, etc.