On the road it'll be about £5-£17 per night.
In Ayacucho and Atalaya it'll be about £20-£30 a night.
In Lima it'll be about £30-£40.
In rural areas about £2-£5 a meal
In towns about £8-£10
Beer: £2-3 (maybe a bit more in Lima)
Pisco sour £4
Fuel and repairs
Fuel: £5 per tank, up to £10 in very remote areas
Mechanic: About £5 for oil change and service