Close down estate agent a business?

We have 2 issues here and are totally confused and have been told so many different things. We have an immobilier business here in France and when we originally set up the business we were advised to start with agent commercial status. After a year of AC, I applied and was given my own Carte Professional to set up our own agency, my wife was to continue as a conjoint collabarateur. As the property business has taken a downward spiral I have been working at a French university as an associate professor PAST, my wife also works there now on a freelance basis where as I am on contract and salaried.

We would like to know how we go about closing down our immobillier business and what affect it will have on our employment status here. I have been told I might lose my Carte Professional? What can I replace this with to satisfy the current requests of the university?  As I am a PAST with the university I have to provide them with my tax status each year as a self employed person. We feel we need to close the business as we are not making any sales now and haven’t for the past year but still paying out money for it just to keep my Carte Professional.

We are involved in a problem with the RSI. They are now seeking back payment for my wife of cotisation 2008 €2712, 2009 €2795, 2010 €2821. When we started we only had one RSI in my name to reduce the cost, we have asked our accountant and been to the RSI on many occasions, to try to sort it out but don’t seem to get anywhere. Our question is if my wife is a co-joint collaborator why would she have to pay this much as we were told she would be covered under my payments? It all seemed to change as soon as I was given my Carte Professional in 2008.