My intention is to live in the basement, rent out the remaining bedroom to a long term roommate, and run the upstairs as a full time STR.I'm aware that the City of Littleton has strict short term rental regulations, but they do allow STRs as long as I have a license and I am occupying the property.  

I know the tools aren't always 100% reliable due to bad data so I'm curious if anyone here as experience with STRs in Albuquerque.It also seems like STR regulations aren't super strict at the moment - need to register for a permit and comply with various rules around occupancy limits, acknowledgements, etc - nothing too crazy.

Presumably my gain will be much (less) on the second sell transaction in CA.Are there any regulations on how long I must hold my 'new' CA property before selling it (and going out of state) to avoid CA taxes on first transaction? 

Have you thought about pending regulations in those areas? 

In most municipalities approvals have a few year shelf life and in the event new regulations or new zoning bills are passed you could lose the benefit of the in place zoning/development procedures.

Very few lenders do well in the space due to the risks involved (novelty, rules/regulations, etc...). 

Here are the 7 material participation tests as outlined in the IRS regulations:1. 500-Hour Test: The individual participates in the activity for more than 500 hours during the tax year.2.

In my case I operate using a Regulation D 506c and 506b, and operate a personally guaranteed debt fund. 

I am agnostic on geography other than looking to stay East of the Mississippi and out high tax/high regulation states. 

In general you should start looking for a single family house that has zoning regulations that allows to ADU (Accessory Dwelling Unit) or can be setup to house hack.