I'm currently working part-time as a secret shopper this summer and have come across these jobs where you have to drive relatively far. The distance can be anywhere from 25 to 60 miles (on average, but possibly more if you want certain jobs). Pay is negotiable. This is what makes it worthwhile for me. And I'm wondering how one goes about calculating the value of wear and tear on your car if you travel? Obviously, travel expenses should factor in gas and time spent driving. But it's the more nebulous value of wear and tear (and mileage accrued too??) that I'm wondering about. What do you have to take into account and how would you do the math? For the purposes of a very simple situation, let's say I need to travel 40 miles for a job(s) somewhere. My car gets roughly 40 miles per gallon (35 for city and 45 for freeway). And let's say it takes me exactly one hour to get there. Based on that, I can obviously come up with travel pay for the hour drive being at least: cost of 1 gallon of gas = $2.25 (where I live) + 1 hour of labor (let's use $7.50 minimum wage to make it super easy here) eta: Doh! Didn't even realize min. wage in USA is $7.25. Oh well, let's keep this anyways. So far, that's $9.75. Let's round it up to $10.00 to make it easy. For a round-trip drive, I would value it at $20.00 minimum so far. But that $20.00 does not factor in wear and tear on my car, as the more I drive, the more my tires wear down, the quicker I'll need an oil change, the faster various parts (break pads, etc.) where out, etc. But there are so many variables to consider with wear and tear. What should I take into account and how might I value it for that 1 hour one-way/2 hour round-trip drive? Any ideas? Thanks for your feedback.