You know, I'm going to disagree that this is a worthless topic and here's why. Though I still don't have a driver's license, if I raced in SCCA, I'd love to strap into one of those Spec Racer Fords, or whatever they are called. I would like some kind of sportscar-style racing because I don't want to live a racing life with stock cars as my focus like most other American racing stars. As I "investigated" from the SCCA's website, you can actually rent race cars to be used for racing competition. So to say that you can't rent a car for some number of races or days is pretty much pathetic. If you want the most competitive stuff at a less-than-stellar budget, you'd want to rent rides. And if you can't do that, then at least have a chance to get a used car and modify it to the best of your ability.
To add in a catch, let's say you can only do this in the Beginner races, some Amateur races, but definitely NOT in the Professional races. I don't think Ukyo Katayama would want to rent a Toyota GT-One to beat the Audis at Le Mans. I don't think Sam Hornish would want to borrow the McLaren-Mercedes F1 car of the late 1990s to take on 2004 technology. And I don't think Colin McRae would want to borrow a 1994 Toyota Celica WRC to edge out the Imprezas and 307s of today (hell, Colin needs a ride SOMEWHERE. He's a hell of a rally star that recently re-upped his deal to race next year's Paris-Dakar rally). So, those are my views, and it's nice to answer your thread in the most honest way I can. Take care, alright?