Have a new to us 1990 Wellcraft 233 Eclipse. Boat is mechanically solid, but I plan on redoing the 3 back flat cushions and backrest over the winter. I have shopped several local shops and around $600 is the average I have been quoted. Although the price isn't terrible, I can buy all of necessary wood and vinyl for around $200. My question is how hard is it to upholster flat cushions and make them look right? I do not have knowledge or access to a sewing machine, so everything would have to be tucked and stapled. It's a nearly 30 year old boat so the job doesn't have to be perfect, but I do want it to look nice. Any advise would be welcome and much appreciated.