What location?

Franchises manage their own employees and commission targets. At corporate locations, policies are centralized, but enforcement of policies is largely dependent on local management.

I can't speak to specifics in either case (not knowing each individual franchise's policies or being specifically familiar with Budget's corporate policy), but in the industry in general, incremental sales revenue for each agent is totaled up and then divided by the number of rental days to arrive at an "average incremental revenue per day" figure (commonly called in the industry a sales "yield"). Often, companies/locations will have a tiered commission system, so the higher the yield, the higher the commission payout. A figure at a company I'm familiar with paid their top agents a 15% commission if their sales yield exceeded $20, and there were several agents in that tier, a couple of whom managed to take home about $120K/year or so.

There isn't usually a minimum quota per se, just that yield figure, and so if the agent's yield drops below a tier threshold, they stand to lose quite a bit of money. Also, agents with poor yields can be reassigned to other non-sales positions or even let go.

Note that Enterprise does not pay their employees a commission, but they do brainwash them into loving the company so much and wrapping their entire identity up in the company and then believing that the key to their future success and promotion is to sell well that they can almost be more pushy and underhanded than the other companies that pay commission...