Re: power inverters??
It has already been done back in the 70's and 80's. A lot of guys used to run 120V power amps or other high powered equipment, mostly PA type amps. It reminds me of the Terminator Herse with its huge EV speakers and Crown (?) amps.
'65 VW Bus
MA Hippo 122, (2) Aura Sound 8's, (2) SoundStream 6.5 coax, (2) Alpine Type-S 6x9's [rear fill], MBQ DSC1500.1D, RF 501X
'02 BMW 330xi (AWD coupe), every option
Harman/Kardon 12-speaker System Option + Dayton HO D4 10" and PPI Ion 650.1 in sealed box
And many more car audio goodies in storage