It's never too late to save! ^v^
If you just travel alone or in a small party of 2, you may find expensive to travel into Tibet as a Tibet tour is sold as a whole package including not only travel permit, but also tour guide, car with driver, hotel and etc. The main cost is on driving and tour guide due to the long distance between each place in Tibet, without any doubt that the spending will be high if car and tour guide's cost not shared. So, the best and most smart way to travel budget friendly in Tibet is to join in a group tour with like-minded people.