Planning for 2nd Visit on B1

[winner2007]

Hello Members,

I got my B1 in 2007. I travelled in Oct 2007. After that I set up a my own LLC and bought some properties. Now, next month i am planning to travel regarding the filing of taxes and negotiating with new deal for my own LLC.

Now, again do i need any invitation letter from some one working in my own LLC ?

Or what exactly required at port of entry in US ?

Regards