It's a dilemma because you know your stuck with it for years once it's on. We recently painted our cedar exterior. Started by agreeing on a general colour and then buying a series of sample pots. We finally decided on dulux colour bond dune. Amazing in itself as we rarely agree haa. It was a nice mix between beige and grey. We bought the 10 litre tin and went to work. After completing one wall I thought the paint was taking a while to dry as it wasn't getting as dark as the sample. My husband thought it was because of the lighting. I took a piece of wood and painted the sample which we loved and the paint from the 10 litre can together and yes they were a different shade. The hardware store had accidentally mixed the sample pot in double strength. It was all fixed up and we really love the result. So it was Dulux Colourbond Dune. I think it would be perfect with your roof colour.

I agree but my comment means that my opinion is that colour and the way to find out would be as you say in person at a paint store but I reiterate that I have a very trained eye for colour and can only go by the sample above the rest is up to the home owner.

As a former art restorer and now retired I am proficient at mixing colours, I agree with the two above me taking the pillow case is a good idea and the other thing is to do is make sure that the grey has a blue touch as some have a green touch or a brown touch etc so it is possible to get the wrong mauve grey which has a red/brown base to the black and white to achieve the mauve/grey, overall the paint store have people who will help you pick the right colour as often a colour on a small sample looks a lot different when applied to a whole wall. Good luck

Your floor and other wall colours are great but Red (orange), black and white are very harsh together, the wall cabinets either side of the range hood have been badly installed, they should have been built to the ceiling. My suggestion is because the kitchen is small, I would remove the cabinets either side of the range hood and then run a row of white cabinets across above the sink to the end of the bench top. Paint the walls white or a soft grey, the range then becomes a stand alone feature. You didn't mention what the splash back material is but I would consider a clear mirror splash back along behind the sink and up to the base of the new white cabinets so that you're not just looking at a wall. cheers