Seems like a good idea in theory maybe not in practice. 

HELOC for down payment is a good idea, if you can't fund the entire purchase price + rehab amount with the HELOC a combo of HELOC + hard money is a great way to get started.

I have people who have been stationed there before, so I have a decent idea on areas to look in around the base.

But given I've paid for snow removal like once ever, I don't know what I should offer someone who is not a "pro" and already has an idea of their rate. 

All that being said I don't know about if a salt hot tub is better per se, I know it's better for your skin and I'd say perhaps if you're in a very health conscious area like Joshua Tree, some folks might be attracted to the idea of a salt water hot tub.

It’s a good idea to work with a qualified intermediary and a tax advisor to ensure everything is structured properly and you’re clear on any tax implications.

If you have no idea what is going on with this capital call, then the bias should be "no" until you understand what is going on and believe that is the best possible use of your hard earned cash. 

@Izraul Hidashi I’m not claiming to know how the entire banking system works but I feel that I have a pretty good idea.

Starting with local credit unions is a good idea.2 - I recommend starting your search with a Realtor who specializes in working with investors.

If the seller isn't responsive, then do like the idea of telling the tenant you tried, and see if they can get some free legal assistance from a tenant resource center.It is a good reminder as closing approaches to ask the seller to keep tenants updated on the pending sale and when ownership is scheduled to change.