paying fees

When renting a unit what are you expected to do? Is it normal to sign a contract and pay half of the weekly fee and the remaining 30 days before arrival

It depends on the agreement. Many owners don't want to wait until 30 days before the stay to receive full payment. Some want 100% at time of confirmation. Some want 50% at confirmation and the other at 90 days prior. It is negotiable as long as both parties can agree.