Not sure how a group buy would go? Fibreglassing is a labour intensive process, its not done by machines...
I would assume with 1 only set of moulds you can only make 1 set of panels at a time... so wether you make 1 or 100 panels I would assume they would be the same price... The front guards I think where about $200ea... I thought it was fair

Who's keen on 1000 2dr sedan fibreglass doors? Remember they most likely wont de legal for road use...