the hardest part is the rolled R, for me it was anyway. i did eventually get used to it, most southern and eastern european languages have it.
bulgarian's voicing rules makes it so you don't have to stop between syllables at all. in dutch they have similar rules but bulgarian takes it to an extreme.
Will people understand if your R-rolls are bad? I never aim for fluency. I have a trick, which is basically "talk too fast for my pronunciation to matter." And I know its annoying! But it works... Usually.
they can generally understand if you can't roll well, it's more about the vowels that makes it hard to understand.
