It can work, but rarely. The international flight price has been very well globalized.
What used to work very well is to rent a car through a foreign website. I live(d) in the US and was planning a trip in California for a few weeks back in ~2015. By going through a major car rental company's UK website, I literally halved my cost.
I didn't have much luck with this trick last time I travelled though, unfortunately.
We visit France every year-ish and French automakers [1][2] vastly undercut long-term rentals from rental agencies by selling you a car with your promise to sell it back to them at nearly the same price (difference is the rental price). You are only ever out the actual rental price. We regularly save 1-2k EUR on a 3+ week rental unless we book the rental literally 6m+ beforehand. Kicker is that $0 deducible CDW is included, and the terms are quite generous.
The only downside is last-minute cancellations will cost a non-trivial fee, but even those can be mitigated through insurance.
Do you know if there is anything like this in the US? I've considered 1-3 month "trips" in the US, but the car rental ends up being quite expensive (to the point at which I've considered just buying and reselling the car). I'd be happy to front the full cost of the car if I was able to get some guarantee on the resale value, and didn't have to deal with selling the car itself.
It can also happen to work via the phone if it doesn’t online. I was trying to book a one way rental from Bergen to Oslo a few years ago. Avis Norwegian and USA website showed some insane price, but when I called up Bergen airport Avis they quoted me something less than half the price.
Side note if you ever find yourself up that way it’s hands down the most beautiful drive I’ve ever done in my life and I’ve been driving in Iceland, Switzerland and other parts of Norway several times
What used to work very well is to rent a car through a foreign website. I live(d) in the US and was planning a trip in California for a few weeks back in ~2015. By going through a major car rental company's UK website, I literally halved my cost.
I didn't have much luck with this trick last time I travelled though, unfortunately.