I would have to give you this answer:

It all depends.

I doubt that you will be able to sand the stripes off without damaging the paint...but who knows 'til you try it. It will also depend on the skill of the guy doing the work.

Spot repairs never are a 100% success, so if you have the old damage spot repaired, and the damage from sanding, spot repaired, then you will have a car covered in "bandaids", and it will not look like new showroom paint.

I can't say if it will save money doing it this way, either. Depending on the reapirs, and the shop doing them, you will pay $150 -$300 per repair. By the time you add them all up, you might have been able to repaint it all, and have a nicer job.

If it is more important to you to have original paint, than nice paint, that's your choice.