i only use mat to reinforce, i always use fleece as it can absorb about the same and it's cheaper. you can get a fleece blanket from wally world for $4. I get my resin from marine supply store or boat shops as they sell a gallon for $20.
i used bondo brand mat and resin... Some people talk bad about ti for big prejects but for door pods its just fine... and do your first layer fleece and really pour ont he resin and get you a good base then you only need maybe 2 layers after that.... just be sure to take your time sanding...