Location will be a major factor in determining the potential strategy for the park, as well as projecting how the park will perform.  

I actually have done personally exactly what you're describing - HELOC on primary residence, use that to purchase new primary, move into new primary and rent the previous home(4 times in 5 years).

But I raise it incrementally and give them a respectful notice in person.

The VA loan assumption can be done by a non-va buyer, as long as that person selling does not use their VA loan benefits on their next purchase.

I personally found I’m good at it if it’s a simple job, normal easy walls, but hire out if its 2-story height, painting cabinetry, wood windows etc as they are a all a big pain.

If you're going to manage a GC, make sure to meet them in person and avoid paying for the entire job upfront (typically for smaller jobs, you will pay half upfront, and half at the end). 

I'll be around this weekend if you want to meetup and talk in person while you pass through. 

I've been knocking on the BP door forever now.Let's not forget that I'm the only person ever to call Dorkin a Wanker during my BP interview haha

One being that I personally needed liquid resources(cash).  

I've done several house-hacks personally with different strategies as well and have helped many clients do them in Pinellas/Hillsborough/Pasco/Manatee counties as well so if you have questions let me know and I can give you a rundown of your best options based on your preferences.If you don't want, or don't need to house-hack, then you have a couple options and that is going to depend on your goals, savings rate, and other details.