[Pro Sites] Variable Level In Pro Sites

If there's already a way to do this please let me know, but I would like to create a pricing table that includes an unpriced "Enterprise" level, that says something like "variable" where the price is, and "Request a Quote" instead of "Choose Plan" for the button. If the use selects that plan, they'd be taken to a contact page instead of sent to checkout. I could then manually apply the level to the custom project so they get access to everything, but I'd also like to have some way to charge a recurring hosting fee, ideally through the same system.