I know nothing of the boat, but a quick google search...
50 YEARS OF REBEL SAILBOAT HISTORY
Looks like a heavy-ish centerboard boat for a 16 footer. But given that its a centerboarder weight distribution will be essential to keep you from swimming.
I'd recommend learning on a keelboat first then trying the centerboard as well. Other option is to learn on a very light wind day...
What else will you need?
Life jackets for everyone (properly sized for each person).
1 tossable cushion
I'd recommend a boat hook (floating) or with clips for the boat.
Sailing gloves if you otherwise have girly hands (like me I punch keys for a living).
A motor would be a huge bonus (that sized boat you can get away with a battery and a trolling motor, no fuel to deal with).
Check all the lines to make sure they are not frayed or split or ragged out...
Same with all the wires (stays).
Check the centerboard lifting line/mechanism to make sure it works (not sure how easy that is to do on the trailer).
Now the trailer stuff...
Check tires for pressure.
Check tires for dry rot
raise each wheel up, spin it, make sure the wheel spins freely, and doesn't sound like marbles in a metal coffee can... if it does, it's probably time for bearings, or at least an adjustment and repacking.
Check lights on the trailer.
Check the winch, make sure the line/wire is in good shape and the winch works well.
I think that's a basic list.