membership site for karate club

My son (16!) just got his first dan in Wado. The guy who runs the club needs a better website but when I look at what he needs/wants I see a problem: he needs many of the features I associate with both sports clubs (e.g. membership payments, terms, variations, etc) and CRMs (e.g. mailings management, links between people and clubs) etc. However he doesn’t have either money or IT skills and the last thing he needs is a site that needs external support.

In reviewing drupal modules I don’t see a an easy way to meet his needs and so my advice has been to do facebook and use messenger (he’s a wintel user, poor guy) for mailings.  If a bunch of clubs got together they might be able to pay somebody some money to help, but I don’t see an offering that fits.  My question, therefore is, do you?