So she failed and now she's demanding.

The truth is, you've been fortunate and haven't had to deal with a difficult tenant until now, so you haven't learned the hard lessons and you failed to prepare for the inevitable nonsense that landlords have to deal with.The law gives you 30 days to deal with the deposit, but you chose to wait and hope the problem would go away.

For reference sake, we have one mortgage at 7.5%; one at 5%; and all other financing below 4% with an overall portfolio weighted average interest rate of 3.785%I don't care too much if you have 5 properties or 500, but I'm curious if others have gone through this thought process at some point in their real estate investment journey and if so how did you make this decision?

I know there's AI doomers and boomers, it's definitely going to carry some weight but when the boomers push this narrative it's not without a lot of issues that aren't being recognized.For one, the power for this to happen would require massive, and I mean massive, energy capabilities that just aren't ready right now from a data center level.

That being said, most part time agents fail and you also have to think about your clients best interest.

Not only are they trying to watch out for there safety, but hey they are bringing up a very valid reason of up keep on your property just as if you had an appliance fail, you go fix it, but only this situation is more reason to give you more service/money made/good review if you show that you give somewhat of a care in the world if the people that are paying your bills are in good hands.

Otherwise if buyer fails to pay, seller has to incur legal expenses either to take back their ownership through deed or to assert a claim against buyers other assets (if there are any). 

I'm a newbie to all of this and I will either fail or succeed ! 

I daresay that, for conforming loan, credit is pretty much pass-fail and not hard to get where it needs to be in most cases (my doing what I mention above)... but income is what really matters, once credit is "pass" how much will your income allow you to qualify for?

If you fail to make your monthly house payments to the bank on time, that reflects on the Seller’s credit.