I did a bathroom fit a coupole of years ago. Part of it involved installing a sink vanity unit that was supplied by the customer. In fact the customer supplied everything including tiles. I have had a call telling me that the sink vanity unit has failed. The manufacturer has aknowledged this and supplied a replacement. However they will not fit it. Now the customer is expecting me to go back, take out the old one, disconnect plumbing, re-shape a new worktop, re-connnect plumbing and re-fit the unit. All for free as I did the bathroom installation. If I had supplied the sink unit in the first place then fair enough, but as I didn't, I only supplied labour to fit client's parts, and, none of my labour or installaion has been at fault, where do I stand on this?