get some medicinal in cali or arizoner..
Erm, what?
How much did it all cost if you don't mind my prying?
That's not really prying
Flights to the US are around 500 GBP from Heathrow (up to around 1000 GBP from other places in the EU), car hire is around 15-18 USD per day (I picked the car with the best mileage per gallon, not the absolute cheapest) and petrol is around 3.50-4.50 USD per US gallon (that's around 1.05 USD per litre) with remote places having prices up to around 5.50 USD per gallon (Yosemite, Death Valley) for those who don't fill up their car when they should have done. I used Google maps to estimate the driving distance, and it is quite accurate to add around 10% more for getting lost and deviations.
Accommodation wise, Curry Village in Yosemite is 60-100 USD per night + tax (around 10%), Grand Canyon is around 150 USD + tax (it's quite good to stay in Williams, which is cheaper), and most of the rest of the places were 30-60 USD. If you plan to stay in Moab, book in advance, everywhere else we either booked 1-2 days beforehand or just turned up.
Food wise, if you don't really care what you eat as long as it doesn't look dodgy, then expect to pay 10-20 USD for breakfast and 25-40 USD for dinner (we had big breakfasts and skipped lunches). Since you don't say where you're from and could be from Europe, I will warn you that some food can be very fatty (which made me quite sick a couple of times on the first trip), but places like Subway are always reliable as they're the same as here.
So, for us, the first trip cost around 2800 USD and the second around 670 USD, both excluding flights and hotel in San Francisco/Oakland as those were covered by work/sponsors.