Volvo: 1987 Volvo 240 DL, volvo 240 dl, brake pads and rotors

Question
I recently purchased the subject vehicle and I would like to know why the brakes in the car squeaks. Every mechanics tells me that they are new that I have to wait until 5,000 miles and then it would stop.  Is this true?  
The driver side window does not go down (it is power) they said the relay switch inside the car needs to be replace.  To change the relay switch on the car, is it something I can do myself? Please advise.

Answer
Morena,
If you have the brake pads and rotors replaced using Volvo parts you are less likely to get brake squeal. I have no idea if after 5K the noise will stop, it might be worth a try.
The switch in the left door panel pops out and the switch pops out of the switch pack also. Common repair. Carefully pry out of the main pack and position the new switch as the old one was.