Not saying you need to know if it is 99 studs or 100 studs, but roof... plumbing... electric... fixture budgets... etc.

This is like a forced savings where these funds will accumulate until you need to make a Capital Expenditure (roofing, replace hvac, road work, etc).Getting private money lenders at 4% for 6 years is very unrealistic.

Capex is big things like roof replacememt, HVAC replacement, etc.  

Given the last time it was purchased was 1984, there could be some major repairs needed in the not so distant future such as roof, heater, electric, plumbing.

At this time I would Sell two of my rental houses in order to Buy my friends two houses, on the lot next door, in a bad neighborhood, because I can get them for $30K under Retail, after a new roof and electric.

It doesn't quite meet the 50% rule but I'm paying it off in 15 years instead of 30 and I could always re-fi or get a HELOC to get some of my cash out if a major expense like a roof or something popped up. 

@Michael Dang I used to work with MBCI in Houston on metal roof and panels for my projects, but it's been a while.

The roof was replaced last year.

I always hire out drywall, roofing and gutters, even though I can do them.

I had painted living room prior after a leak and she actually asked my painter-without my permission-to paint hallway also.