Quest in condo

Got a contract to buy a condo in colorado springs. Looking at the crawl space, all the service is quest gray pipe. Condo built 1984. I am going to ask the owner or to replace with
Uponor Pex because we offered way over market due to lack of inventory and this unit has great view and otherwise really nice. All the plumbing is really accessible throughout the crawl space, no demo.
Two baths a kitchen and laundry . Comments? I am guessing this will cost about 3 -5 k for a licensed plumber. I did my own ski cabin repipe for about 350 in material and had a helper.

Your insurance company might not even write you a policy with polybutylene plumbing still installed.

The seller should know that already.

What about fittings in the walls