If not then you need to use financing like hard money or private money. 

I knew about that because he lived with me then.  

I indicated the cash flow was calculated using 50% rule then subtract P&I.  

Mine doesn't, and as long as the dog doesn't have a bite history then im ok to rent to anyone with any breed.

Then once you have some cash flow coming in and some experience you can look to commercial properties.

It has not been easy, but if it was, then anyone could be doing it.

As the seller I would pay for the energy audit, do the analysis on the work to be done (cost vs savings) and then market the home with a prepackaged improvement contract that would meet lender guidelines (solar, EE windows, etc). 45 day close to allow for enough time to do loan and obtain permits, occupancy COE+2. 

Having an inspection report in hand will set the tone, and then from there you can decide which issues (if any) you want to get a quote for.

My question is, could we take out the HELOC and then use that to move to a new primary residence and keep our current home as the investment property?

If you have not, you do not need to set up an LLC/ See if you do one or two, then worry about setting it all up.