Then, if you can trend over time you'll want to see where the "path of progress" is going/moving and attempt to buy in that path of progress to gain some appreciation in the future.

I think with the time you’ll spend working on this, you could find 2-3 existing parks to buy in the meantime and not need to take anywhere near the same risk  

Investment Info:Single-family residence buy & hold investment.

This works with any type of appreciating property such as real estate, stocks, etcDepending on the appreciation rate, you can potentially see asset values double every 7-14 years.Likely around 7 years if the appreciation rate is 8%Likely around 14 years if the appreciation rate is 4%If you buy something for $100,000 and it appreciates to $200,000, you can potentially take a loan on the $100,000 appreciation which would not be considered a taxable event.However, be mindful that you are paying interest on the loan and you have to payback the loan but yes, it would not add on to your taxable income.

They are just going to use their 2nd VA loan to buy their next one while this one is tied up. 

Recommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

Our initial goal has been to buy a property every time the Army relocates me (roughly every two years) and rent it out afterward.

Investment Info:Small multi-family (2-4 units) buy & hold investment.

Split the $20 to buy yourself lunch and dinnerIf you are on the road, daily per-diem should cover a lot of your day to date living costs.If they send you on the road, you can potentially airbnb your house.Best of luck!

Use the HELOC on cash-generating opportunities like flips, then use the cash generated to buy long-term buy and hold investments.