So... price almost always denotes intrinsic worth when it comes to old ukes? Hmm.
Of course not. Price is a function of market forces. Generally speaking, instruments that are in high demand cost more. Demand often equates with quality, but there is not a direct correlation. For example: when I was a lad in the 1970's, just starting to play guitar, you could buy any of a dozen 1950's Les Pauls from the classifieds for around $350. They were old guitars, and people wanted the newer, better stuff. Those same guitar today sell for $10K. Did they really improve that much over the ensuing years? Nope, the demand just went up, either because of the vintage mythology, the acquisition of disposable income by buyers, or maybe an appreciation of how good those old guitars were. In any case, the guitars are the same; it's the demand that changed.
In the early 20th century, mandolins were designed to be played in chamber groups and mandolin orchestras, where the goal was to blend in. Lloyd Loar designed the F5 mandolin for Gibson in 1923, giving it a punchy, urgent tone that really wasn't all that popular with player of the era. 20 years later, Bill Monroe purchased a Lloyd Loar F5 and made it the centerpiece of Bluegrass music. Suddenly, EVERYBODY loved the Lloyd Loar F5 sound, and it may be the most copied design in history. Original Lloyd Loar F5 mandolins sell in the six figure range, despite being factory-produced instruments. They are remarkable instruments, but their value is driven by their association with Bill Monroe and the remarkable fealty of bluegrass players.
I could go on, but I think the point is made. High price doesn't mean good quality, but good quality often means high price. If I sell my Waterman for $10K, it's still a Waterman. Early instruments often sell for a premium because of their rarity, but that doesn't mean you'll like the way they sound. I was enamored of the old Gibson oval hole archtops, because I thought they had one of the most beautiful guitars design I'd ever seen. I payed fairly large bucks to acquire a 1915 L-4, then sold it within the year. It sure was pretty, but it had a dull, thuddy tone that didn't appeal to me at all. Perhaps worth the money as a collectible, not worth the money as a playable instrument.
Several posters have provided the best advice: if you're interested in vintage instruments, get out and play as many as you can. Nobody can tell you what you like. I bought a 1920's Oscar Schmidt uke from Jake Wildwood for relatively small money that sounds awesome. Awesome doesn't have to be expensive. I also have a 1930 Martin Style 0 that cost a bunch more that also sounds awesome. Often awesome *is* expensive.
But you're the one who has to love it. So why listen to a bunch of strangers?