Two prices, two distinct options
R134a and R1234yf are not alternatives to choose between on price. The correct option depends on the vehicle's system. This website does not infer refrigerant from age, make, model or registration, so an unknown refrigerant should lead to an enquiry.
Describe the cooling problem
Explain when the change began, whether it is constant or intermittent and what happened after any previous work. Include unusual sounds or an earlier regas that did not resolve the problem. Those details help the team discuss assessment without assuming a diagnosis.
What still needs confirming
Confirm the gas allowance, leak testing, any repairs and appointment length with the team before agreeing the work. A recharge is not a guarantee that an underlying fault has been identified or resolved.