Despite price rises and comparatively high costs in Sofia, Plovdiv and along the coast, the essentials remain inexpensive. If you are camping and buying food in local markets, you can live with 20 EUR a day.
Staying in modest hotels or private rooms and eating out regularly, 40-50 EUR should be sufficient, while on a daily budget of 70 EUR or above you can enjoy a very good life, staying in mid-range hotels and taking taxis everywhere. Only if you require business-class accommodation will you need more than that.
The most unpredictable factor is the cost of accommodation, which varies from region to region, as well as depending on the facilities, age and ownership of the place in question. Private rooms and B&Bs can cost anywhere from 6-20 EUR per person and hotels are equally variable, with two-star places costing from 10-30 EUR per person, three-star hotels from 40-80 EUR, and four-and five-star establishments from 90-150 EUR.
There is less variation in the cost of hostels (5-10 EUR), mountain huts (6-10 EUR) and campsites (4-6 EUR), but their standards vary even more.