Do i still owe landlord despite signature "paid in full"? Is my landlord harassing me and my mother?

It doesn't matter so much what an attorney on AVVO tells you but rather what matters is whether your landlord sues you and what happens at trial. ...

I'm uncomfortable living with my roommates, but the landlord will not let release me from the lease. What can I do?

Bad situation; however, it is not the landlord's fault. Your landlord is being reasonable by offering to let you find a replacement.

My apartment lease does not state that smoking is allowed. My wife and I's neighbor below us smokes. She admitted it to our LL.

Can you breach your lease? Yes. Will you get sued? Maybe. Will you lose? Probably, unless all of the leases preclude smoking and your landlord...

Can former janitor refuse to return keys for nonpayment if fired for negligence (ie leaving back door open 2 nights in a row)?

Can someone refuse to do something? Yes. Whether it makes sense for you to pay an attorney to deal with the situation is a better question.

Can I still collect Dec rent when my tenants are being evicted by the 23rd of Dec?

A judgment obtained in November shouldn't include December rent. That would require another suit.

After giving a friend over 6 months to remove a grand piano from my home, is it considered abandoned and may i sell it

Missouri has an unclaimed property statute. Research it and follow it or have an attorney assist. Good luck.

Work things out. Even if you had a legal right to preclude the guest, what are you going to do about it? File a lawsuit, then get a court date a...

Is this wrongful termination?

You've described facts supporting your believe that the termination was unfair but not illegal.

Hostile work environment

Your post is difficult to follow. You seem to be complaining about unfairness but not discrimination based on membership in a protected class...

Quit my previous job I'm entitled to unused pto?

Consult with an employment attorney. There are facts to be proved, such as whether there is an employment contract and what it states.