Not sure where the OP is getting his Michelin tires from but a new set of their tires for my F-450 and F-550 pick-ups run in the $3,000.00 range. Larger coach tires run in the $600.00-$800.00 per tire range for 8 if the coach has a tag axle. Plus mounting and balancing. Figure around $7,000.00 for tires all said and done. For $2,500.00 you might pick up some 10 year old M's with some tread left on them. I personally only run my tires 6 years regardless of tread on all my vehicles.
A few years ago an acquaintance with a custom million plus dollar custom coach had it broken into and they thrashed the inside, the hydraulic slide entry door damaged to gain entry, lots of custom foreign woods used on the interior. Coach used to belong to a band. Coach started life as a mobile home for a band when touring.
So he decided to have a driver who worked for him at the RV Park he owns drive it back to the factory and fly him home to get repairs made. Driver looked over the coach and found the tires to be suffering from tire rot and declined to make the trip till the tires were replaced. 2 fronts were newer so they stayed. All rears, 6 tires had to be replaced. $5,000.00 later the road trip was back on.
