FL Renters did not pay us rent

Renters sent a check for less than 1/2 the rent saying he was in financial hardship and would try to 'catch up'. We called a paralegal and they said to return the check and give them 10 days to pay rent and include ( per our lease ) $50 for late fee. They haven't paid and the 10 days is quickly arriving. What do we do next?

Payday Loan question

I received a phone call from a collection agency claiming that I owe for a $100 payday loan I took out in 2000. I live in the state of MO and the loan was taken in the state of MO. I do not believe I owe the funds - I'm sure I paid it back but of course it's been so long ago I can't find the receipt I received when I paid. Is there a statue of limitations on something like this?

visitation

My husband has 2 kids with another woman. The children are 4/5years old.He has them the 1.3.5.weekend every month. In all the years we've picked them up the mother Never calls to check on her kids, never asks where we are going. She claims she has NO IDEA where we are taking them. Her lawyer send a certified letter which we had to pick up at the post office but forgot to and now she and her lawyer think we are lying about our address.but we are not.This weekend is my husbands but since they think we are lying about our address they are refusing to let us take the children, for saftey concerns. Can my husband still go and pick up the kids with his child support documents? The address on them IS where we live?

Barter for rent

I own a small 5 unit rental property and would like to have someone live in one of the units and act as a handyman to take care of the rest of the place. Can I legally do this?