I see as sort of like the "no commercial vehicles, etc" rules. 

We have a 6 unit multifamily he parking is all open and each unit has one assigned space and can have two vehicles.

@Louis Aller HELOCs are a good vehicle to purchase another property I think you should use it to your advantage.

Why would you bother with less ROI than "easier" vehicles such as Mutual Funds? 

I have two scenarios I want to address:1) They fund 100% of the deal as a loan. and2) They want me to manage their money and invest it for them in real estate.What vehicle would I use to have them transfer me the money, without incurring taxes?

An rv is act actually a vehicle and is titled as a recreational vehicle.  

Then I miss out on seeingtheir vehicles and seeing how they are kept - a good clue as to how your property will be taken care of.

I really don't understand why the government requires someone to have a license to even explain a security, or an insurance policy or even a vehicle after so many transactions in one year to have a license to do so and not require any person transacting more than two RE transactions, of any kind, to have a license.

@Wayne Brooks, is there a vehicle whereby the agent can point out to the bank that the unit is "original" and the comps may be off?

However condo's can be a good investment depending on price you paid, appreciation potential, HOA's, and cash flow.The real problem you are having isn't your investment vehicle but rather your temperament and landlording style.