Dentist quoted me for treatment but now this has gone up, after they removed my teeth! I would be grateful for any advice?

Q. Hi I have been going to a cosmetic dentist for three months now after 20 yrs of dental phobia! They advised me that all my teeth needed to be extracted and that I need full fixed bridge upper and lower on 8 implants at the top plus 4 mini implants and 6 implants on the bottom. What started off as a quote for around £15k worth of treatment (not including the £3.5k fir extractions and temp dentures ) has risen to £35k – but this is after my teeth have gone. They have told me to arrange my own ct scan – no clue how I do this and are not willing to reline my awful temp dentures as they are very busy. Does this sound right? Grateful for any advice, I am 40 in good health don\’t smoke never had but have family history of periodontal disease quite severely. Thanks. ,