Seems to be a very good price for this retrofitted lock.
Bought myself as it is compatible with HomeKit.
According to specs work with: Apple HomeKit, Android, Amazon Alexa, and Nest (Silver)
Saw Gumtree sales in the $200 mark and some on eBay @ $299 so this seems like a good deal so posting to share.
Unfortunately have no idea when this expires, and also as usual make sure its compatible with your existing lock as it is a retrofitted solution.
I bought something similar to that on kickstarter (https://candyhouse.co/) and it doesn't work. looks cool but most of the times it doesn't have the power (force) to turn the lock. it is now stored in the 'bought but won't use' box.