What's the problem with radiator price for Motorhome?

I paid $1700 for new copper core for my radiator in 2007. It also included labor to move tanks from old core to new core and delivery to/from my house. Price of copper was going sky high at the time. The radiator in my unit is pretty big and very heavy!

The shop made out pretty well on me since they told me the core had been in inventory for quite a few years so they bought it when copper prices were much lower.