I have been told that to get a really great mouser, you should feed them and pet them. That way they are content and happy and see you as a member of the family - hence in need of "presents".
I wouldn't buy a cat though...... there are so many unwanted cats now that need homes. I went to the local Cats Protection when I moved into my smallhold because my husband (all 6'3" judo fighter of him) is afraid of rats. I adopted three wild feral cats to live in the barn. Got them at 6 months and was told that they would never be friendly as they hadn't been socialised to humans at a young age.
As I write one is lying in front of the woodburner being petted by my 18month old and the other two are outside wanting to join her.
The cats are all great mousers (and snakers, and volers and froggers
).
The Cats Protection have loads and loads of great cats just waiting for a good home. They microchip and neuter them and just ask for a donation........