The main consideration is what to do with their kit.  They tend to have one or two kayaks and paddles each and need somewhere reasonably safe to store these - though in most cases they can just stay on their car roofracks or on their trailer.

Kayakers go and get wet on rivers, lochs, or sea all day every day and end up having a lot of wet clothing as a result.  Some items of kit don't absolutely have to be completely dried out as they'll just get wet again - this includes helmets, boyancy aids, and spraydecks which most paddlers will be happy to leave hanging dripping somewhere secure outside or under-cover - for instance in a shed or on a washing line.

Items such as dry trousers, jackets, and shoes ideally need to be dried out overnight in order to be ready to keep folk warm again the next day - these items could do with hanging space somewhere warm and inside (note that they will be pretty wet at first and will drip onto whatever is below - often hanging them over a clothes horse in a bath for a couple of hours is the way forwards!).

Underneath, paddlers usually wear a layer of thermals and a fleece - these tend to get pretty wet and the best solution is often to be able to wash and dry them.