He could try to evict you for non-payment of rent.

Your minimum down payment amount for a 2-4 unit will be about the same as an often required 20-25% down payment on a co-op.

My guess is they missed a payment, then started up again. 

And unless you go into some very rough areas, you won't find double digit cash returns.

so i had zero debt or interest payments on it while it was being fixed up. 

The didn't live within their means, accrued a lot of debt, and it eventually resulted in them not paying rent and being evicted.Consolidating debt reduces their payments so they have more money available, but it doesn't automatically teach them to live within their means.

As lenders, well issue a prequal/preapproval letter if we've analyzed your income, assets (bank and brokerage statements to establish that you have the liquidity to afford the down payment, closing costs, and reserves), review credit of the guarantors, review the relevant experience to ensure that we're not throwing our money away on newbies that are wandering around in the dark, and have put together a reasonable plan of attack for the project.

save enough for a down payment and invest in loge term hold.  

Take the larger down payment and put it into something bigger, which lowers your %equity in the property but still keeps the $equity and the cash flow is now going into the larger property.

This would lower your down payment requirements, lower your interest rate, lower your property taxes, and MAY make you exempt from state income tax.