I've nothing really to add this as everyone has covered my opinion. Donedeal is full of bad breeders and puppy farmers BUT for every 3 or 4 of them, theres a good breeder. I've gotten dogs of it before but it took a long time to root out the bad eggs and find the good ones. It's a great resource for experienced dog owners/buyers but for the newbie, it can be a minefield that may eventually cost them thousands in vet bills and ultimately lead to heartache.
They should really have a FAQ for potential owners on the first page, as another poster here already said.
What annoys me more than the puppy farmers is actually the owners that want to get rid of an older dog cos they havnt got the space etc but are looking for huge sums of money. If, god forbid, I ever had to get rid of my dogs they'd be free to good homes and I'd be VERY picky. Or worse again, the people who advertise the likes of "9 month old akita for sale. Great dog but i havnt got the time for him/her. Will swap for xbox360" I'm not exaggerating, thats an actual ad I reported a while back and there are always more swaps coming up. Some times swapping dogs for different breeds. Sorry, rant over