Speak to the local car dealerships in your area and ask them if they would be willing to supply a few luxury cars for a test drive course that you can then use as a fundraising event.
Set up a series of cones in a parking lot or other suitable venue, then charge attendees to take a test drive around the route you've set out. People will be eager to see what it's like to drive the ultra-luxurious vehicle that they'll probably never be able to afford. (Or will they?) Allowing dealerships to send salespeople down can encourage them to get involved if they think they might shift a few cars in the process.
It's worth considering including some niche vehicles in the line up to add a different spin to the event — think limousine or electric car, for example. Be on the look out for vehicles that most people don't have the opportunity to drive. The dealership you're working with might agree to bring a rugged or off-road type vehicle, which work would perfectly with an off-road style obstacle course (you can set one up yourself or hire one).
You could also see if there is a local military base or VFW hall that can supply you with some military equipment too — after all, who wouldn't want to pay a few dollars in return for a ride a historic tank?
