I'm preparing to install a Jacuzzi Luxura 5 whirlpool bath. This is
a 32" x 60" tub, not one of the big ones. I'm undecided on whether
to install the optional inline water heater. The one offered by
Jacuzzi, the RapidHeat unit, costs about $370 on the street, as
nearly as I can tell.

So, two questions. One, can these be installed through the access
panels
after the tub is installed, thus allowing us to learn if we really
need one at all?
Two, are there cheaper generic inline heaters that would work?

I am pulling wires for the separate heater circuit just in case.

TIA

Ed