Inspection costs?

Hello! I have recently registered a Grand Vitara 2.4, Ez. 3/11, about 38,000 km. In March I registered the one in a Suzuki contract workshop for the 4th annual inspection. Now the friendly staff asked me if I would like to have the air conditioning maintenance and the brake fluid change at this appointment! The inspection + climate + brake fluid should cost about 600,- Euro there; after the individual prices I did not ask! Question: What can the pure 4th annual inspek can I have these two additional work done there without any concern or would it be much cheaper if I had to do it elsewhere? You can get brake fluid change for 25-30 euros and air conditioning maintenance from approx. 60 euros in various free workshops. Thanks already! Greeting Fliegentod