@gohan Lol you're absolutely right! I should have thought of that earlier - thanks!

@gohan I don't use their gateway as it's a bit clunky although it does have local control. Like many I use a Samsung smartthings hub which doesn't cost much more as it's often heavily discounted - pairing with the ST hub can be hit or miss though.

@NeverDie Just do a search on sites like gearbest.com or Banggood.com for Xiaomi smart home. The common sensors go on sale fairly often but they're usually less than $10 a pop.