I so adamantly tell interior designers to get insurance (DO NOT WORK WITHOUT IT!!!) that I also get a lot of questions about what insurance to have.  I'm not an insurance professional and do not know your specific situation so I can't tell you what insurance is best for you.  However, here is a primer of insurance for interior designers so you can talk to your agent about what may be best for your business.

Get as much coverage as you can, the more the better.  You may think it's overkill until you need it.  

A few reasons you must have insurance: protect yourself and your business, to avoid a lawsuit, computer crashes, server explosions, natural disasters...