Hi cesmeresident - and thanks for the heads-up about the booking agent, suncar, who do seem to operate in Bulgaria as well as Alicante, to which the letter of complaint relates.
However, the letter to the telegraph is just one letter from one dissatisfied customer and although it should, of course, start to set alarm bells ringing, I think that if you trawl the internet then you will find similar letters about practically every car hire company or booking agent in existence, probably concerning most hire locations.
Online reviews of car hire companies are also available (for example, see here :-
http://www.reviewcentre.com/ ) but it is also not unknown for competitors to post derogatory reviews on the internet just to discredit rival companies..
That's why I have found this site to be so useful - You can, by reading around the carefully organised topics, (thanks MODS

) gather a (usually reliable) host of information about almost anything.
AND it's supplied by 'friends', to boot! Ermmm... well, 'people you know'...
Ah..... well... 'other people who come here to MyBG'......
It's jolly useful, anyway!
Thanks again!