A build is an appointment of about an hour, in person or over a video call for anybody not in the city.
We work in the usual three parts. The top is what greets somebody for the first ten minutes and is gone by the twentieth. The heart is what the scent is for the next two to three hours and is what people will remember it as. The base is what survives to the evening and clings to a collar until it is washed.
Then the concentration, which is simply how much material is dissolved in the alcohol. Eau de toilette at around ten per cent is lighter and closer to the skin. Eau de parfum at eighteen to twenty per cent lasts longer and projects further, and in this heat it is often more than people expect.
We write the formula in grammes, give it a batch code, and make it. Then it sits for twenty eight days. You get a two millilitre sample of your own build, and the bottle is a separate decision made a month later.
We will argue with you during that hour, politely. That is what you are paying for.