It is not difficult to install a heat pump if you can silver solder the
joints and can vacuum the system down before charging it with R-22 Freon.
R-22 is a controlled substance so you may have to have that portion done by
a certified tech. You can often purchase a "Scratch & Dent" unit from the
local wholesale distributor at a nice savings. Be certain to purchase a
thermostat that exactly matches the heat pump or wiring it correctly can be
a challenge.

Don Dando