I have a 2011 Mercedes-Benz C-Class. The air-conditioning was giving out hot air on the nearside so I took it into the local independent who I use to service the car. They have found that whilst the air-conditioning is working, the flaps which control the flow of air to the air-conditioning evaporator or heater matrix are not working on the nearside. This could be due to a faulty motor, which they have quoted £200-£400 to fix of it could be fault with the flaps or the linkage in the heater box, which will entail stripping out the complete dashboard and could run up a bill of £2000 due to the amount of labour involved. Having regard to the age of the car, what would you advise and how would you judge the reasonableness of the suggested costs?