I know there are many great tax breaks too from my listening to the BP podcast so I presume that owning property in a company is the best way forward in the USA, much like it is in Europe, is this true and if so, what company structure is best please? 

Specifically, I’m interested in learning:-How you structured the financing (e.g., terms of the HELOC, overall investment strategy).

If the property contains a residential structure, you can do any necessary repairs to make the property habitable (but not upgrades) and the VALUE (not the cost) of those repairs is an additional charge if there is a redemption.

Speak to a real estate attorney as I cannot really give legal advice on this, but I have seen clients of mine structure this as a leaseback. 

I do know that some of the supply houses are great for lighting/electrical/plumbing/HVAC/etc.

LOL  If there's going to be problems down the road, their advice or forethought as to the planning/building of the structure, at least the flooring/layering on top of the existing structure, is going to be sooooo vital. 

I think transunion has stopped supplying information in states where they don't believe they can comply with local law  but they don't have an actual set of states listed like some services.

There’s an electrical supply company that lists stuff on EBay and the cost was 1/3 what it would have been from our local electrical supply company.

If there are lots of active rentals, then it very well isn't below market as there's substantially more supply than demand.

If my property was residential in nature, I would seek a residential in a nature fee structure.