Will it increase your equity a substantial enough amount and soon enough to make it worth it, versus using the existing equity you have now?

The price went from just under $3K to just under $5K which is still supposedly a substantial discount from what new clients are paying.  

These can, of course, be influenced heavily by how you and your partners have "used" the facility as an asset over the time you've owned it. 

As the Owner/Builder Disclosure statement reads "[The property] may not be built or substantially improved for sale or lease. 

If you buy through a wholesaler, you might save substantial money but will probably have to come up with quick cash.

However, I don't know if I would substantially raise the rent in that situation under all circumstances..

Line of credit using equity from existing properties.Second lender to borrow down payment.Partner with another investor that has funds.Find partners through your sphere of influence (family, friends, colleagues)Rob a bank

I would like to find something with modest risk/reward as not losing my cash is more important than a substantial ROI.

If all the licensed Realtors got together and "decided" that such-and-such was a "D" neighborhood, that in itself would harm not only that neighborhood and the people in it, but also people buying houses in the area to boot.Historically, there was a time when people with licenses (read: in a position to influence buyers and sellers) would do exactly that.

We paid some closing costs but instead of just buying the property for 155k (which could have lowered the value of the neighborhood and influenced an appraiser to give the value of the purchase price as the market value - which happens a lot) I bought it for 190k (which was more realistic of the true market value).