Medical insurance will be included in your salary if not, about 6% is reasonable. The housing expenses can be cut significantly.
Share a rent of a nice flat with friends close to where you work. This will cut bills and transportation.
A very nice small flat in nice neighbourhood(Vitosha)  for 2 will be around 300L per person. And the bills will be about 60 per month - inc. water(5), electricity(20), hot water(20), internet(10).

The food cost is greater than you think. You'll need at least 10lv. per day and in real life it goes to about 400 L per month.

The entertainment and clothing budget is extremely low.
For example a new pair of shoes will cost you around 150lv.
And don't buy anything cheap, you'll regret it in a month or two.

So 1200 per month a realistic goal. You can live even with 800 but you'll have to cut all the clothing, entertainment, savings, etc. less than 1000 is hard for more than 3-4 months.

Rent and bills 	300 rent, 60 bills
Food 	400 L
Transportation 	40 L
Entertainment and clothing 	200 L
Debts and Savings 	100 L
Misc. 	100 L