I had a load of info on maintenance and payments as I did some research for someone last year. I don't remember the ins and outs exactly so don't want to give you in correct advice now but will dig it out next week and post it [can't do it know]
But the bottom line seemed to be for owners to take over the maintenance and management responsibility's themselves. Which is a mine field, time consuming and hard work. Just getting the right number of owners together for the AGM for instance.
I seem to remember banshie [I think that was the members name] were very good on this subject and so in the meantime do a search for her on here.
Also I found that that the wayback machine has some of the Mybulgaria's missing threads cir 2012 /15, so it might be worth checking there.https://mhlegal.eu/
used to give very good advice via a blog, sadly they have moved out of this sort of
area of interest, but I think some of the information they posted still exists but it's not on their website any more.
Although it could be out dated but maybe not, depends if the law has changed in the intervening time.
A quick google foundhttps://mhlegal.eu/blog/major-amendment ... ement-act/
from 2011 would be worth a read, but check if the law has been updated since 2011.
and this would be worth reading https://mhlegal.eu/blog/collecting-outs ... ndominium/
as it discusses the maintenance fees for the comment areas and is from 2013 Which might make interesting reading for your friend as it seemed [if my memory is correct] to exclude non resident owners from some maintenance liability. However its in everyone's interest to maintain their developments; just not be forced to pay exorbitant amounts of maintenance or management fees
Also https://mhlegal.eu/blog/maintenance-com ... um-owners/
I seem to remember the comments section was useful.
Hope some of this is helpful and not out of date.