Buying an "Assignment of Contract" deal - what to look out for?

[Steven LaLonde]

Hi Everyone, 

I just had an offer accepted on a duplex which is listed by a realtor as an "Assignment of Contract" and they require it to be a cash deal.  I will have my lawyer review all paperwork etc., but I am just wondering:

A). If anyone has any advice or things to look out when on the buying side of an "Assignment of Contract" deal?  

B). Is there any way to require the seller to disclose to me what they acquired the contract for before planning to "assign it" to another buyer?  Property is in NY.  I want the property either way, curious more than anything. 

Thanks for any advice as I've never bought an assignment of contract deal.

Steve