Reporting on my own quest to build up my capsule wardrobe, especially in light of increasing my days/week at work come January. :)
When I assessed via the Starting from Scratch wardrobe (which really has more clothes than I need, as I can spend a lot of days in jeans and yoga pants around here :-) ), I realized that my base neutrals were already black and charcoal, and although I thought my accents would be red and blue, when I actually pulled out all my tops, I realized that I had very little red (and a little green), but mostly blues and purples. I had almost no white tops (like you, Bracken Joy, I mostly wear colours!), 1 skirt (that I don't wear often) and a pair of dark skinny jeans. 1 charcoal cardigan and a few merino crew-neck sweaters.
So I have been on the hunt for a black cardigan (I do have a really heavy wool one for when it's really cold, but it's too heavy for most of the year), a black skirt, another white top, black shoes, and possibly a dress in one of my colours. I also have wondered about a cardi in one of the accent colours, as recommended by the Vivienne Files.
With some time to shop in the bigger city today, I had some success! I found a white top on deep discount at one store, a blue merino cardi 40% off at the Gap, and then closed my eyes and bit the bullet and bought the black skirt that I liked months ago and didn't buy because it was almost $70 (!!!!). After MONTHS of looking for an alternative, I am buoyed by the confidence that I will wear this regularly for years to come and that it will go with everything I own. Then I brought home a pair of black pants and a sparkly charcoal grey cardi for possible Christmas wear (to dress up everything else that I already own) from Costco. Will return if I don't like them.
Anyway, I'm really just sharing all this because I was SO pleased as I shopped because I could stay focused, ignore many items that might have otherwise tempted me, and best of all, I avoided the major angst and difficulty deciding to part with my money because I just wasn't sure if I would wear a given thing, or what it might go with in my wardrobe. I KNOW that everything will work and match. I'm also more confident spending a seemingly unmustachian amount on a particular item, because I know that I my costs per wear will be low and I won't have to shop again for a long time to come! I'd rather buy what I need and stay out of the stores to save money than buy cheaper things that I will always be trying to replace because I don't really like them or I can't wear them with enough of my basics.
DDD and others, I can't thank you enough for the resources you have shared!