I've always operated out out assumption that majority of ships, including the largest of capitals, are actually dirt cheap and made mostly of tinfoil. That would explain why everyone and their dog can build some.
Actually, making a half-decent battleship for a somewhat resource-limited faction would be easier than making a half-decent snubcraft. Once you don't have to deal with miniaturization, constructions gets quite a lot easier.
Making top-of-the-line warships is another story, though.