I would advise against choosing surgery based on price alone. Price and location should be secondary considerations to quality of the work you'll get.
I would also advise against listening to the advice of people who only copy and paste the opinions of others. Most people say you cannot get a great hair transplant in the UK, only say it because they read someone else saying it; it's a vicious circle based mostly on bullshit (and a few genuine horror stories, which have nothing to do with Dr. Rogers). A lot of it seems to stem back to about six years ago where a number of clinics were the subject of a negative publicity campaign with some shills making posts and wild claims all over the place.
I would not be surprised that if per-capita there were far higher numbers of bad surgeons in the US than the UK for example.
The biggest problem the UK has is as far as I know there are just two surgeons who only specialise in hair transplants, Dr. Rogers (who I've been to and know personally others who have had excellent results) and Dr. Farjo. I cannot comment on the work Dr. Farjo does, though I've not heard anything bad directly.
Beyond those two all I've heard are horror stories, and my own experience from short listing clinics indicates that the horror stories have some credibility. Clinics who sell surgical procedures as if they are selling used cars are best avoided, this applies to *any* surgical procedure.
Bottom line, clinics which specialise in hair transplant are a much better bet than clinics where the surgeon is doing hair transplant on the Monday, tooth veneers on the Tuesday and botox parties the rest of the week. Those sorts of "circuit clinics" are a nightmare, you don't know if you're going to get a decent surgeon, or some hack fresh from med school. Sure, you'll get a great price, but you might also end up losing all your donor hair (refund or not, nothing can replace that).
Also, make sure you can meet your surgeon up front, and the clinic has their name over the door. Those guys rely on their reputation to get business and not shiny advertising campaigns.