Been lurking here for awhile now too.
My wife and I have been talking about doing this for some time now, and going through all the different ways that we could get into RV'ing like we want to.
As a truck driver, it just felt natural to me to get a rig ourselves and modify it to pull an RV.
Now my employer is talking about selling the rig I have driven for the last several years in order to upgrade and I may be in a position to purchase it from them.
It is a '00 Freightliner FLD 120 w/ 72" Condo, Cummins N14+ turned up to a little over 500hp, with an Eaton Autoshifter
If we get this the plan is to build a deck to haul a Jeep (have to sell my Burb as it's just too long to haul like that) and pull a fifth wheel in the 40ft range behind it.
The details are all swimming around in my head and occasionally I start to put it all down, but that is the general idea.
With our families all over the US and this being a "small" combo compared to what I'm used to pulling I really hope this is something we can pull off.