Easy steps to guesstimate how much epoxy you'll need.

As you know fiberglass cloth has a weight rating.  6oz, 4oz, etc....  That stands for how much resin it will take to wet our one full yard of cloth.  So one yard of 6oz cloth will take 6 oz of resin which in theory gives you a 50/50 resin to cloth ratio.

The method I use is a little easier due to not always using an equal number of yards.  If you have a digital scale, weigh you cloth.  Whatever the weight is in ounces or grams, use that much epoxy PLUS a little extra for waste.

Can't help with the second part but if your boat doesn't sit in the water all day everyday than Id use something like bright side as an alternative.

 Thanks!  Thats a great rule of thumb will give it a try this weekend.

(I built one last summer) 16oz sounds like a good estimate.   Be sure to do it with a partner.