There will be fewer places to stay en route than on the Rickshaw Run, but other than that, prices will be similar.
Accommodation will generally be in roadside tents which should cost you around Rs.200 per person per night. You can find hotels and guesthouses in the bigger towns which will vary, but likely Rs.500 to Rs.1500 will get you something not shit.
Food and water prices are generally a little more pricey than mainland India, but it's still relatively affordable. Water is likely to cost you Rs.30 - 50 per bottle, a thali around Rs.200 and a bowl of maggi noodles or momos around Rs.100.
You'll likely need around £100 - £150 between you for petrol. Maybe more if your wee beastie is as thirsty as a Glaswegian dock worker.