I agree Hilda at one point I wanted to paint our south facing sitting room in a pale greeny grey. We were staying with friends and much admired the colour of the bedroom we were given. Asked the name etc, (Swansdown, Dulux I think) bought a matchpot and were amazed when it came out a bright icy blue!
If you can get hold of a proper trade colour chart, the ones with the numbers as well as the sometimes daft names, one of the numbers used gives you an indication of how much grey there is in the base colour. It is sometimes quite surprising how much grey there is in a pink shade, for example.
How big is the room anneey and what is in there that will have to stay, furniture, carpets etc?