Also "set up" is the verb form, and "setup" is the noun form. Similar:

Log in with your password, and login will be complete.

The signout process causes the user to sign out.

I will pick up some rocks with my pickup truck because someone asked for a rock pickup.

Yeah my only real experience selling domains are on sites like flippa who take either/both an upfront listing fee or a percentage of the sale price. If you're not doing the latter you can almost definitely charge more for unlimited domains :)

Really like the idea for the site, nice work