ebay is cheapest and best,
i got mine from ebay
what you need is,
some old clothes, old gloves, measuring equipment nothing, mixing bowls nothing plastic, (well thin plastic)
medium pile rollers. not the synthetic ones they disintegrate, scissors, dry day, patience,
what you should do it
mix up enough for 1m2 about 200ml of resin and tiny tiny amount of catalyst and put this over the area you want to fiberglass, then lay down you 1m2 piece of mat, and role it in gently so its nicely stuck down,
then mix up about 700ml of resin and the necessary catalyst and then really work it in, so both layers are gelled together and have a good adhesion, use a roller to get the most of it on, then a brush to really push it in to all those nooks and crannies,
then continue for the rest of the van,
when its all dried apply your topcoat, pretty easy, you can do this in one go, its self leveling so if there are no major deformities it will look nice,
when ordering ask for something to add to the gelcoat to make it non slip and also what colour you would like
instructions come with the stuff you buy anyways so set aside a weekend to do it any youll be fine