Could that be part of the reason for their failure?

Failure to pay rent or breach of lease.

This headache might be alleviated by replacing the filters ourselves from now on... so we eliminate the possibility of this being the case of AC failures moving forward, but we'll see.

The penalty is a failure to file penalty.

One investor finds success while another finds failure following a similar strategy.

The penalties for this return start at $10,000... and that's just for non-negligent failure-to-file or filing an incomplete or inaccurate 5471.

When personal growth is the goal, the only failure is not trying.For whatever it's worth, many successful people constantly raise the bar and say "good lord this is too much!"

Less chance for failure in my opinion.

They also have 2 dogs allowed under their lease, and they have a third dog now.My PM said even with moratoriums lifted, this isn't enough to evict - the trash, the failure to respond to notices, the lease  violations, the harassment - so we got them to sign an amendment to their lease to agree to 8/31/21 at the ending date (rather than spring of 2022), and immediately sent a notice to vacate. 

I don't think it will be  the difference between success and failure..............but introverts probably have less fun.