What to do after I received a deal from an owner to my proposal?

[Leo Tsang]

I got a call from the owner whom I sent a proposal to buy his property in Florence NJ. He is interested in one of my proposal which is a cash deal at signing with a monthly income for 30 years. I am happy to receive his call but now I am nervous because I dont know what to do next. 

One of the things is our agreement over the phone is not currently bound by any legal document (or under contract). And he will have another open house in this coming weekend. So I hope all of you who are experienced in this forum will be able to help me with the following questions:

1. I know I need an attorney to put all these agreements in black and white. But before that, should I find an agent so s/he could get me the deal under contract? 

2. If so, should I use my own agent? or I should contact his agent? 

I am actually leaning toward calling his agent so he can represent both of us, the seller and buyer while I contact my attorney. If I contact their agent, I would also like s/he to find tenant for me. Do you think it is wise to do so?

3. The other thing is I have not looked at the property which I would like to once I got it under contract which I will be able to walk out if there are major issues that I find it not worth buying the property afterward. Do I have the same kind of right to do so if I simply go thru the attorney?

Many thanks.