Access while rent is not being paid

Access

Hi,
I have been waiting for a month now and my tenant still hasn't paid even part of the rent. She has received my termination notice , accepted it and signed a receipt for it.
The contract was from Nov 1st 2012 to May 1st 2013.
It looked amicable but she is now not replying to my text messages asking when she could pay the rent .
I would now like to either sell the property or have a new tenant and she accepted some time ago to let the agent to take measurements for advertising and viewing.
I would also probably have the bathroom renovated.
I don't know if her attitude is going to change and my question is:
What rights have I got to have the agent show people around and /or
have the bathroom renovated at reasonable times?

Many thanks