I have a time-sensitive out of state lead where an investor son wants to buy the owner mom's house in arrears. She'll hold a silent second for me bringing the loan current and I'll be a 50/50 equity partner. What are my risks and their solutions? 

For example, he'll put me on the deed, but that just exposes me to him potentially abandoning the property and leaving me with the full mtg obligation. Or the due on sale clause kicks in. What do I need to consider and how do I protect myself if I do this?

That said, would you take a small 26k 2nd on a 435k ARV buy hold for 50% equity with current purchase/rehab = 75% ARV? If so, how do you protect yourself?

@Geoffrey Pierce Unless there is a huge upside and unless you have seen the property and know the area and your partner I would not enter into such an agreement. Speak with a good RE attorney to advise you if you do decide to enter the agreement and protect your self with the contract verbiage etc...

 I've worked with him before, and he's mentoring me. He's a Tasmanian Devil in that he's got ridiculous energy and never stops dealing. About 100 deals under his belt. I know the area roughly. Lived in the area for ten years. Don't know the exact neighborhood. 120k equity as is, and has investor offers for 350k, but he's a hard core buy/hold guy. Will bring his contract to my atty. Thanks.