How to put an off market property under contract?

[Alexander Ball]

I found a seller who's looking to sell a couple of their duplexes off market in West Virginia.  I did this through direct mail.  I'm going to take a look at them later this week and will make a formal offer.  What I don't know how to do is actually put this deal under contract. I've bought multiple rentals but always with a realtor and through the mls, never off market in this way.




1.  Do I need a lawyer or can I use rocket lawyer, etc?
2. For closing, obviously I need to get loans for the purchase price and I'll also due inspections as well.  But what do they need to do on their end?  Do they need to bring anything to close like proof of ownership? I have no idea. 
3. Is there anything else I need to do or consider? Should I put down earnest money or anything?

thanks