This is pretty spot on.

Also, the reason everything is cheap in northern NH is because there is no money. No one is going to go up north to build houses cheap so everyone else can be rich. OP says he'd have to make his own money up there, and he's not wrong. He'd also be making a lot less to be competitive.

No matter where you live, it is likely your income will scale with the cost of living in that area. The exception are some of the higher CoL areas where people will pay to live in paradise (ie: Hawaii and some parts of California). The only people getting ahead are the people living in LCoL areas but work remotely for HCoL or VHCoL area businesses.