Fitted by
The people who fit these every week.
Anyone can drop-ship a lock. The difference is whether the person selling it has stood at your kind of door before and knows what goes wrong.

A real install, not a stock photo
That is a KS250 on an aluminium door with the existing mortice still in place. It is the most common job there is: the door stays, the hardware changes, and the customer stops carrying a key.
Book a fitting.
Auckland wide, including ranchsliders, french doors and aluminium joinery. Old hardware removed and taken away, first codes set up on the day.
Fitting it yourself?
Every model ships with a paper template and a step-by-step install guide, and the guides are free to download before you buy.