Thanks for taking the time to answer me!The document check in France before our trip is actually a really good idea, but do you know if it is possible without renting a car at this time? Literally just go there so they see the documents, validate the Gold Plus account and leave?

Considering additional driver fees, as [MENTION=155928]trueblu[/MENTION] said, actually there isn't any in California, so we will be able to have as many drivers as there are seats in the cars without paying more! Well, hopefully everyone doesn't have to subscribe to two credit cards each...

What the agent told me about the additional drivers credit cards makes us pretty anxious about the rental. You seem to have had a great experience with your Challenger R/T upgrade, but maybe that was because you are in your own country and a regular renter? They might take extra precautions with tourists, and we really just can't take the risk not to be able to get the cars because we don't have the right cards. Hopefully nobody will ask them, but it would be such a shame not getting the cars we booked (as they are such an important part of a 3000 miles roadtrip), or maybe worse, to get them but that only the main driver could drive them because he was the only one to have 2 credit cards, because I've never seen one man drive three cars at the same time

About National, Sixt or even other companies, we actually can't compare them with Hertz yet, as we are able to see the prices from Hertz for our dates in August 2020, but on the other companies' websites you can't see more than a year in advance. We actually think the prices Hertz show us are reasonable for the cars we want. Without adding CDP codes, it represents around 5500$ for a Suburban, and two cars from the Adrenaline Collection for three whole weeks of renting.

One thing is sure by now, is that we are going to get two credit cards for the main driver. They are likely to be Carrefour Pass credit cards (Carrefour is the equivalent of Walmart, here in France), they are real credit cards and Mastercard too. But we really really would like to avoid getting everyone from our group to get two credit cards as well, just for identification purposes...