Never buy a condo as an investment to rent out....its just overall going to be a more difficult investment vehicle.  

An RV is a vehicle, a mobilehome is a residence.

My wife and I want to retire soon and this seems like the vehicle to get us to that point.

Is there enough space for 2 or more vehicles?

don't buy things that give you "bad" credit...like a depreciating vehicle.

vehicle mileage is always a good dedection, assuming it's not a "company" vehicle.

Since we use our personal vehicles for doing rental activities, and have racked up quite a bit of mileage - there is a section in Schedule E instructions about unreimbursed partnership expense (https://www.irs.gov/pub/irs-pdf/i1040se.pdf).  

When is it legal to get rid of personal property/tow vehicles?  

Could perhaps be interpreted as being mortgage fraud.This is definitely mortgage fraud.For self employed people, you need to deduct your normal and necessary business expenses.Where you have a little bit of wiggle room is in the personal expenses that you can choose to make business expenses such as Home Office, Mileage on a personal vehicle or the portion of your cell phone or internet bill that you allocate to business. 

I know purchasing property from a relative is prohibited inside a retirement vehicle, but want to make sure it doesn't apply to the solo 401K loan as well.