I have not owned or played any custom ukes in the brief time since I started playing the ukulele. That hasn't stopped me from drooling over them from various custom builders. In fact, I already have 2 on order with two builders who has sterling reputations among uke fans.
The first one I ordered, about 3 months into uke playing, was a Glyph mezzo-soprano uke built by Dave Means. Dave does some outstanding work as you can see from his uke gallery and has one of the best reputations among custom builders. The result of that is a waiting list close to 3 years long. When I placed my order in May of '07, my uke was scheduled to be completed around March of 2010! I just figured I'd better place an order sooner rather than later or I may never be able to get a Glyph. Choosing the mezzo-soprano size was partly influenced by economics and partly influenced by the desire for something different. I knew I wanted something bigger than a soprano but not quite a tenor at the time, so it was either a concert or the mezzo-soprano. Since the mezzo-soprano is a custom size Dave had dreamed up, I thought it would make for a great custom ukulele.
The second custom uke I ordered was from Kepasa Ukuleles, built by Kevin Crossett. Kevin is a relatively new builder who has been repairing instruments for many many years. Some of his customers had posted on various forums about how wonderful his ukes are so I checked out his website. One uke in particular caught my eyes. It was his Little Mac model. Previously I had seen an Po-Mahina Island Jazz uke from the cover of Mel Bay's Fingerstyle Solos and thought it was really nifty. I liked the looks of the Selmer/Maccaferri guitar design and these ukes looked very interesting to me. So I contacted Kevin about the Little Mac and learned that his prices were very affordable for custom built instruments. In addition, he would be able to accommodate my request to add a D-shaped soundhole and a cutaway body style. That made it a no-brainer. This uke is scheduled to start building in January of '08 and should be done by March. It'll be a nice birthday present for myself next April. :)
Even though I have not even received my first custom ukulele yet, I've been thinking about getting a custom built long scale (18 inch scale) tenor. I know I want one made with a spruce top and possibly koa sides and backs. I also want it to have a slotted headstock. The builder I'm most intrigued with is William King of Chantus Music. People who has played his ukes rave at the sound and playability. He also doesn't appear to have quite the long wait list as Dave Means, which is a big plus since I'm already going to wait over 2 years for a uke. The afore mentioned Po Mahina is another possibility to have a good custom tenor built. Other highly reputable custom builders include Mike DaSilva, and Dave Talsma. I guess by the time I am ready to pull the trigger on an order, I'll have decided which one to go with. If I had to choose right now, it'd probably be William King.
Anyway, as you can see, I have some rampant UAS going on here. I do plan to sell off ukes for each new one I acquire, but it only becomes harder and harder as each remaining uke becomes more and more indispensable. Or something.