i drive 98 volvo v70 changed front brakes and rotors and changed rear brakes and rotor and calipers they were sticking upon fixing i hear whistling every so often even coming down my driveway

You may have done so but make sure that the slider pins are all clean and shiny. Chuck them in a drill and slip a strip of abrasive round them. Replace any that are damaged. Lubricate with silicone brake grease not copper grease.
https://www.youtube.com/watch?v=Xxj3xj5mFxo
As said, check and adjust the handbrake cable. Probably like this.
https://www.youtube.com/watch?v=N0g2FgKOgsE

What kind of pads did you use in the rear? I only use OEM with the builtin shims. Make sure it is greased up good where the pads hang on to the caliper bracket, and the outside edge of the piston.

Only silicone brake grease, of course.
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Keeping it running is better than buying new

Not all that sure what you are asking about. For the whistling, does the parking brake work? Make sure it is working - both engaging and disengaging as it should and not dragging. Did you adjust it when you replaced the rear rotors?

While you're in there to confirm the parking brake, inspect the rear brakes looking for uneven wear of the pads or anything else out of place.

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XC60 / Odyssey

I concur. Check your parking brake adjustment. Visually inspect the other brakes for unusual wear.
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Will I buy another Volvo??? We'll see....