What if the edge of sink leaks     

Sinks leaking is not a very serious problem, it is easy to handle, if the sink can be moved, for example, you can stick a circle of  double side sealing tape on the back side of the sink,  normal your can find in the building material market, and then it is ok to pu  sink back.  If you want to be more safe, you can also use mildew proof silicone on the back sides of the sink.