Denver homes commonly have a separate entrance to the basement, so that is the form ours take.

You want them to be able to access your entrance from both ways.L.

So, having a basement tenant who in reality uses their own entrance and doesn't come into the rest of the house seems risky in the event that I do end up having to face the Code Dept.

Also, if you go this route, make sure you have a separate entrance, and enough parking so cars can get in and out without having to shuffle around.The other option, if you have enough land, would be to build a completely separate dwelling on the property - an ADU. 

This is also helpful for many gated communities with HOA's who now require a list of all guests preregistered at the entrance.

Ideally if you would get the best price if you  have a seperate entrance area of the house you can periodically occupy that and treat the main part of the house as a unit you don't have access too.

There is usually trunk lines from the main entrance to 1, or a handful, of breaker panels on each floor where each panel would service several rooms.You might be able to pull-off an executive suites, mid-long term furnished rental, with little zoning issues ... perhaps under the existing zoning for hospitality.  

There's a sign in the entrance that says if you get the hallway wet from coming back from the beach or pool, you will be fined $100. 

It also depends on your budget, and entrance/exit strategy of choice.

You can go put up a stand at any mall entrance, big banner saying you'll buy homes, and get about same response.