I am going to form a LLC this February.

Do lots of pro forma tests on the properties.

Are the financials trailing 12 month actuals, pro formas, or something else?    

I'd love to see your excel form as well.

The more like-minded investors you meet, the better your chances are of meeting a mentor or a business partner that you can form a mutually beneficial relationship with.

2) Option 2: We form a JV between our existing LLC and the investor.

You haven't really provided enough information for anybody to form a proper response.

the problem you will face with a PO box is that when you will want to form a LLC you cannot use a PO box address in the formation or for the IRS. your best bet is to go to a mailbox center such as the UPS store or the like, due to they are set up as actual address not PO boxes.

Recently he approached me wanting to form a partnership.

Here are a few ideas on how to hunt down the property owners:Search public records (you'll have to subscribe to a service)Form a relationship with an agent (they have access to this info and can you get the owners)Form a relationship with a title agent and they can get you this info for freeTry http://www.propertyshark.com/You can also visit a local assessor's office to obtain the information in-person:The Assessor's office does not provide owner name information on their website.