Are there version control and project management tools which "work well" with freelancing jobs, if I want to keep my customer involved in the project at all times?

What concerns me is that repository hosting providers have their fees based on the "number of users", which I feel is the number which will constantly increase as I finish one project after another. For each project, for example, I would have to add permissions to my contractor to allow him to pull the source code and collaborate.

So how does that work in practice? Do I "remove" the contractor from the project once it's done? This means I basically state that I offer no support and bugfixes anymore. Or do freelances end up paying more and more money for these services?

Do you use such online services, or you host them by yourself? Or do you simply send your code to your customer by e-mail in weekly iterations?