Custody Problems?

I know someone who i met this summer. He was visiting pa to see his mom for the summer. He lives with his dad in Fl. He moved back with his dad when he was 13. He wants to stay living here now but hes only 16 and his dad says it costs 300 to make the court date. He says the reason that he cant just sign him over to his mom is bc he got in trouble up here last year one night. for underagedrinking and curfew violation and poss. of marijuana. He is a very good kid thouhg loves his family and a straight A student. Im not familiar with Fl. Laws but i was wondering if this 300 dollar charge is true bc ifso he will have to get a job to pay for it to come back. Also how long does it usually take for these things to get set up and is it completely up to him where he gets to live???