Assuming that all goes well and the buyer’s good-faith offer is accepted by the seller, the earnest money funds go toward the down payment and closing costs.

Why not joint venture with someone who has money, fix & flip itWhy not rent it out for at least the monthly carrying costs.Why not sell it on a lease option, get 10% cash up front to fund school? 

I'm just beginning but am considering a bigger commitment in the next five years or so by accessing some or even all retirement funds to buy a building (I'm sure people have thoughts on whether or not that is a good idea!).

You also want to see a reserve study and only invest in a property where the HOA is at least 30% funded, less than that is assessment territory. 

Most seller's in a sub-to don't understand the risk they are taking and most lenders have concerns over the overall portfolio quality ratings which has an impact on their cost of funds.

Unless you're in a Class A Neighborhood like Palmer Woods, Indian Village, Sherwood, etc,. the additional rent probably won't support the cost to build:(More profitable to take the build funds and buy another property.DM us if you'd like to discuss more...

In my experience it cannot be used as construction funding. 

As apples to an IRA Hope that makes sense .

He also focuses on getting investors to use their IRAs, or retirement funds to invest.

I would acquire in cash and then refi into longer funding. #4.