Yes it is a flight only but I found that was a really good price from manchester to Varna, it was £165 from Luton to varna for the same period. I did search for holidays also to see if it worked out cheaper to do it that way but no chance. If you can get a return flight from manchester to Varna + hotel for £180 please let me know where as I am going back over in July for a month.
SWMBO has booked return flights in mid September for £128 for the pair of us from Gatwick to Varna with BA.
I hope that their price includes for the allowance of extra tea bags as hand luggage.