Having spent the best part of an hour looking at doorbells in B&Q, we finally picked one that included one battery for the push button, but none for the actual chime unit. Why on earth don’t doorbell manufacturers include all 3 batteries required, or none at all?!
Of course, having originally decided on one that included all the batteries, we didn’t spot that the final choice didn’t include them all.. got home.. and doh! no batteries.. and they had to be an awkward size that we don’t use anywhere else. One quick trip to the local supermarket and problem solved.