One more thing - I've read all comments and still haven't seen anything about heating. Central (or electrical) heating takes a very big part of monthly bills - still it's cold outside so definitely you'll need to account this too. Here is an example of using space heater for 4 hours a day - it will cost about 30-40 leva for a month.

Also the food - on theory you can live with 4 leva per day - you can cook very simple vegetarian dishes and eat only at home. At work you have to prepare something like a sandwich with two slices of bread and one more slice (of bread) to put in between :(

I've always said that bulgarian families that live with an income around 500-600 leva per month (300 leva per person - yes unfortunately there are such low salaries in Bulgaria) deserve a Nobel Price in Economics. And if you add to this family one or two children...

So, I'm not trying to tell you that your initiative will not work - it's just that it will be very hard and of course that you've always an escape plan B. Good luck!