Simon,

No disrespect intended...I love the initiative, but if you have to rent out your car to afford racing, you can't afford racing and you shouldn't do it.

An enduro rental needs to have NEW everything (hubs, rotors, pads, fluids, maybe clutch, tires, etc) and you need to keep on top of those things so you minimize the chance of a mechanical DNF. You also need to have spares, enough spares to get that car back on track WHEN (not if) an incident occures. Suspension, transmission, ECU, etc. You will need rain tires too. You will need a strong contract. You will need to set expectations. Feel the pain yet?

Rental rides that actually MAKE money, require drivers who are willing to pay real money for a seat. With that money comes expectations about service levels - and I am not sure you are ready for what that really means. It takes time to develop a good program. Trust me.

It's just really a HUGE risk for not much gain.