First decide which part you wanna travel..south or north india
South India - Ooty, Kodaikanal ,Coorg or Munnar
North India - Mussourie, Nainital , Manali or Shillong
Some good and cheap Hill stations in North India-
Mussorie
Nainital
Kasol
Tosh
Malana
Cheap Hill stations in South India-
Kodaikanal
Ooty
Munnar
Nandi hills
My friend,
Take an HTRC bus for Kasol from Delhi ISBT.
From Kasol you can visit to Chhalal, Rasol, Manikaran, Tosh, Kheerganga etc.
These places are much cheaper. You have to search proper rooms and restaurants.
You will find rooms/ tents to stay 300-400/ night in each places.