These sellers paid much less than what the going rate it today, likely have no mortgage or low interest rate mortgage and do not need to push rents to market value to cash flow.They get solid returns at their current rental values, have minimal headache with current tenants and they don't need to do major repairs to get their properties sold for a solid value. 

I paid cash and roughly 25% of retail value. 

Investors get stuck and cannot cash out because of tax complications.

If you are on cash accounting, yes you could do that.On the other hand, you are ignoring carry-forward losses. 

However, most of these properties still cash flow well (or enough to cover PITI). 

Bought a triplex in 2011 with all cash in my retirement account.

Where you pick will depend on your goals for cash flow and your budget to buy.

Also, is it a cash out or rate and term refinance?

For those that have invested $10k have you thought about investing that amount with Grant Cardone..

However, you have to be extremely careful financing 100% of the transaction as you still need reserves, closing costs, etc. and make sure it cash flows.You didn't mention if this would be a rental or owner occupied.