Firstly you will need your IP's permission to sell the house and secondly, if you do sell it, any equity will go towards paying your total debt plus fees and possible statutory interest, not just what is remaining on the IVA.
You would be allowed to keep some to pay legal fees and estate agent fees and possible removal costs.
If you struggling with your payments, please speak to your IP to see if you can redo your I&E as it may be too high.
Sharing from experiences of dealing with debt
The greatness of a man is not in how much wealth he acquires, but in his integrity and his ability to affect those around him positively.
Bob Marley. http://kallis3.blogs.iva.co.uk
Can you continue to pay to pay off any missed payments. Your house then remains safe and sound and you can sell once the completion letter is received and credit files are tidied up. At present I would guess there's a restriction on the property and your IP would need to remove this before you can sell.
All the best in whatever you decide.
IVA final payment left the bank on the 26th January 2013...looking forward to a debt free future.