Typically an investment property needs 20-25% down.

Do you typically find most of your investment properties on the MLS or word of mouth pocket listings?

Anyway cap rtes are thrown on here frequently and the way theya re defined on here befuddles me as I am used to the Walgreens / Targets of the world and ( typically A+ tenants in the 5 range A Multi family will get you high 6's low 7's in various markets ) cap rates determine value  eg...

It will be tough to find a HML who can fund the deal fast enough for an auction property.Auctions typically require full payment, in cash, within 24 hours of the end of the auction.You would need to get pre-approved with a HML and have the funds already available.Otherwise you could find a private money lender or partner to take on the deal as well.

Single military typically don't move off-base (at least for the AF) until they are E-4.

With that said, with the exception of high interest debt, it's typically better in the long wrong to use available cash to invest. 

Tax deeds typically wipe out most liens and mortgages with a few exceptions.

Roofing Contractors are typically good at providing a quote on-site or at least within a couple of days of visiting the property, so it's worth taking an extra few days to get some additional quotes.

I'd continue to read the amazing content here on BP but also recommend to attend local REIA's to meet investors; they typically waive the entrance fee your first time around.

There is nothing wrong with that but that is not the typical way to buy investment real estate and you lose the advantage of leverage.