Hi
If you've got rough ground that isn't level, and you're in a rural area, then see a local agricultural supplier who will hire you a compact tractor with a stone burier. Make sure that you have confidence in the hirer to get the spec right, a 1.7m wide stone burier requires about 40hp at least at the tractor.

A stone burier sort of "rotovates" the ground, putting the big stones at the bottom then the loose soil on top. It also has a big wide roller, which when combined with the weight of the tractor re-compacts and rolls the earth flat. You'll still have 3/4" stones on the surface, but either pick them out or roll them in.

Forget turf. Use seed. If you've done the above, you'll have good soil down to 8", and a lawn grown from seed is easy, much much cheaper, and the roots better grounded in the soil. But use good seed - not cheap stuff - you pay for what you get.

Finally, the above is only really viable for lawns above 0.5 acres, due to the size of the equipment. Tractors are great in straight lines, but if it's all turns in a short space they're no good. Try a pedestrial powered rotovator type tool instead...

Hope this helps.