We've always hired through carhire3000, I think they're called something else but google carhire3000 for it, rentalcars.com springs to mind. They are upfront about costs and they are in the UK so you can talk to someone first. It's worth considering getting a separate policy to cover insurance excess, it can be cheaper depending on how long you're going for and how often you hire a car. We've never had trouble with US car hiring in 30 years, they seem less devious than their European counterparts.