If you are not a DIY man now is the time to learn. Get on youtube and buy the tools you need. They are all free from the money you save by doing the jobs yourself. Flush out the braking system. Take it on the road and brake like hell. Flush the system out again. Do the same again See does that take care of the pedal.
If your coolant is not going down then you have nothing to worry about. Keep your eye on that. My guess is a hiss from a hose or radiator or a joint which is getting into you via the heater vents. Anything from the rear would be left alone in the dust. Theres a film on you tube on how to remove the front bumper to clean between the radiators and condensors. I did mine, I am 71 and its a dodle of a job. You can easily check things when you are in there.
Porsche 996 986 bumper removal - YouTube
