Run two DVR's on same service, but different accounts?

I have a Roamio Plus and I'm looking to get a Bolt soon. Instead of selling the Roamio, I have a potential use for it to use for my Airbnb. I want to continue to use on TV service provider (Frontier), but have both the Roamio and the Bolt operate off the same coax while not seeing content from each others DVR (that way the Airbnb people can have their own DVR content but not interfere with my personal content on my other DVR).

Also, are Mini's able to be assigned to one DVR and not the other?