What rights do I have to enforce the rules on the use of home office by a consultant?

My husband and I are owners of a business with 50-50 shares. The office is in our home basement. I have emailed the consultant re: hours he is able to use office, request for detailed weekly time log/duties he has performed, etc. He is willfully defiant with hours in office, not emailing detailed time sheets, bills, etc. He only wants to deal with my spouse. My spouse gives him permission to break hours in office. I caught consultant the other day using our office computer to buy baseball tickets-he was on his cell phone but used our computer to look up seating charts. What are my rights without getting divorced over this?