When do I create a formal business entity (LLC, etc.)?

[John R.]

I would like to get involved in real estate investing and am giving serious consideration to purchase, rehab and resell scenarios. Although, it is hard to ignore (or so it seems) the idea of doing some bird-dogging or wholesaling to get used to the industry and learn. I have absolutely no experience, except regarding purchasing a couple of homes, over the years, to live in. Should I create a formal business entity BEFORE I do anything?