As others have suggested above, try naming your own price on priceline.com before resorting to using miles. I've gotten some unbelievably low rentals from Captain Kirk! You just have to be sure of your dates, as once your bid goes through, there's no going back.
I've done mileage rentals a couple times, where I couldn't find a reasonable price (the big island over the holidays, for one). Sometimes, they're worth it.
Good luck!
Originally Posted by
rtom
I don't have collision insurance for my car, so I might be well-advised to pay for that.
Not sure whether this consideration affects whether I am better off paying cash or with miles for the base rate.
This is a good point. When I did my mileage rentals, I made sure I paid for the loss damage waiver, since I normally use my United Signature Visa for rentals, which provides this extra coverage. Using miles, you get no Signature Visa protection, so make sure either your car insurance company protects your rental car, or pay for the LDW/CDL. I was surprised when I called my insurer (USAA) and they advised me to always get the LDW (or use my Visa).