Opening a Rep office or company in the US (Chicago)

Hi Guys,

I used to live in Chicago for a year and really felt in love with the city. Unfortunately with the bad economy I had to leave but I am ready to come back and live in my dream city.

I have two options.
1. Either I restart a company there
2. Either I start a rep office there.
The only problem is that I am not an American citizen and it is a little difficult for me to know which direction to take with all those visa issues.
Please let me know if any of you guys did experiment this situation.
I will be more than happy to have a chat with you.

Thank you so much in advance for your consideration.
I will be in Chicago by the end of February.
Hope to see you there.

Cheers
Aurelien