Installing a generator in 1999 Roadtrek 190 Pop

[Tim C]

Hi,
I'm new to this and I found a Roadtrek 1999 Popular 190 im interested in buying.
It has no generator and I will be in Florida often so I need AC at night .

Any suggestions ?

How difficult / expensive is it to :
have someone install an Oman generator ?
Or Solar / Lithium ?

Thanks in advance ! Tim