In an increasingly litigious society, I believe a lot of doctors now refuse to do LPA validation. It is, after all, a serious business and even £180, minus costs for the practice, isn't a big sum to compensate them for the risk someone might query the validation at a later date. A doctor could be struck off if they get it wrong.
We paid £120 for Mum's LPAs about four years ago, and I think that was for health and financial. Whether the total cost was £120 or £240 I consider it the best money I ever spent from Mum's resources. Life with LPAs is so much simpler than without.
So... I can understand how you feel, given your different circumstances, but they really are doing you a favour. It takes a while to go through the paperwork and a double appointment was definitely required in our case. My Mum was already impaired though, so it had to be methodical.