If one does a search, with the topic being along the lines of folks buying sails
. Many/most of the key questions & features can be dug up. It's just that it takes a while in order to assemble them all. As different lofts have differing levels of, & styles of fitting out. And, of course, the "Devil" (quality of the resulting sails), is in the details.
Ergo my (abridged) checklist, above.
As, believe me, a quality loft will/can give you a list of choices & decisions to make about your next main or jib
, which is literally, 2+ pages long (single spaced). And it PAYS to work with such people.