Process of closing off market deals

[Vanessa Johns]

I have a newbie question, and maybe I'm just not searching the forums well enough to find this and it's already been answered. If so, I apologize. 

I have done 2 or 3 deals now on the MLS, so I'm familiar with how a property purchase closes when you are working with a realtor. But I'm about to do my first off market deal from a wholesaler, and I realized I don't really know any of the details about how that process is supposed to go. Is there a title search? Do I hire a title company? Do I sign a purchase agreement or assignment, and then I'm on the hook to handle all of that? The wholesalers all want a non refundable deposit, so I would like to at least know the title is clear first. At what point is it time to wire the money?

When it gets down to actually making an offer and giving earnest money, can anyone tell me what the precise order of these details should be? Thank you so much!