Originally Posted by
YVR Cockroach
You could try buying a package in your home country that includes a OW rental + all the insurance. Insurance bought from the rental company at the counter is $$$.
Especially that LDW as mentionned by the OP isn't an insurance, it only waives your liability towards national if you smash the car up.
SLI will cover you against mowing somebody over. I'd rather have SLI than LDW (think about the cost of paying for a person's dismemberment for the rest of their life vs. smashing up a car. [even there i'm guessing the number of times a rental gets totalled is rare].
I think there was a link to an insurance policy which American Express provide for something like 25USD for the whole rental period.