The best product on the market for trailer roof repair is Rubberized Leak Stopper. The sealant will get deep into the cracks to form a secure bond with the roofing material and creates a permanent seal. There product comes with an excellent guarantee and cost about $20.00 per gallon.
If you are going to charge the AC system in your car you will first need to know what type of Freon to add. You should be able to look in your vehicles owner manual or check your repair manual to see what was used. The newer Freon that is used today is R134 and the older Freon is R12 refrigerant.
Make sure you get your brakes serviced once you can tell a noticeable difference in braking power. Failing to do so could be deadly.