Just got back from a day in Boro (I live in Sofia), prices I paid were as follows:
Park the car - 5 Lev
half day ski pass - 16.50 Lev
Nachos and tin of coke (was passed 'use by' date) 15.50 Lev
My view is that the skiing remains good value despite the limited runs but the restaurants and bars are now jut getting ridiculous. There is no business reason for their prices to be 3 or 4 times higher than Sofia, it is just pure short term greed.
Parking around Borovets towards the Sitnakovo lift (black run) is normally 10 levs per day. If you can get back a bit and avoid the police you can park for free but you have to be a little sly. The Samakov carpark just down and opposite the gondola is good if you are there early and its very secure (guys on the barrier) and a similar price.
Actually 10 levs (although it is expensive relatively) is a bargain not to have to spend a fortune and a day in time trying to get your car back from some crook who has towed it away.