Rehabs are subject to "The Existing Building Code" and the extent of compliance is determined by the percentage of renovation work proposed.

Is there a point when you stop saving money and start paying off existing mortgages faster?

I dont know about Atlanta or GA MSA but there are some banks here in WA these days that go upto 95 or even 100% (according to the flyers I have seen) with a full appraisal and other factors like assets, your financial stmt and other criteria but upto 90% LTV is pretty std I think in most cases for a HELOC on a primary residence and 80%LTV on a cashout on primary residence.If its a rental your only option would be cash out refi @75%LTV as HELOCs on an inv prop are virtually non existent anymore after 2008/2009 market crash but you never know.

64 units X 500 a month = 32,000 X 12 months = 384,000 gross(Take away 60% of expected revenue for vacancy, property management, evictions, expenses, etc.)384,000 X .60 = 230,400384,000 -230,400 = 153,600 expected NOI153,600/2,125,000 = 7.2 cap rateThis is IF there is not existing deferred issues with the property.

You will want to make sure that the beam above supporting the roof is in good condition as wellif you are trying to fix the columns using similar materials, you will want to make sure the existing block is structurally sound.

If you are using unfinished flooring your base will be marked up from the sanders, edgers and you may get some unintentional poly splash when coating. also if there is existing hardwood that will be refinished cover it before you paint and careful with the demo guys removing carpet.

Where do you think these numbers exist?

Coinmac (or whatever they're called now -- google 'em) will put machines in there at no cost to you, service them, take the cash out, etc and mail you a check for your cut (they have different profit splits you can negotiate) .If you just have a small building, it's not likey worth the cost of doing a 'smart washer' that can take payment via venmo/paypal/applepay but they do exist. 

The adjusted offer came after the inspection and was far lower than the first and was based on air conditioning issues which didn't exist. 

As an active duty service member you will run into the time old issue of deciding where you want your portfolio to exist.