Probably when you feel that it is too many and it starts to make you uncomfortable in one way or another (guilt, feeling burdened and "cluttered" (similar to feeling sticky and wanting a shower on a hot summer day), sense of stagnation because you hop around too much, too frequent emotions of regret or buyer's remorse, various other forms of stress, etc).
I think feelings are probably a good indicator: if you feel good and happy, and you're having fun, keep doing what you're doing; if there are clouds on your emotional sky, change what you do (or how you look at it). That sometimes works for me.
The short version: It's probably different for everyone. Right now, I accepted that I'll do some more exploring, and decided that at the end of the exploration phase I'd like to have no more than 3 quality ukuleles + one "beater", and preferably less.
Ha, this is like the opposite of the minimalist approach that we discussed earlier!
Mivo is absolutely right about the emotional part. Moreover, I would say that Ukulele Aquisition (or any accumulation, for that matter) will become a problem if you spend more than you earn or need to support yourself and your family or when you're running out of space to put them. Luckily, ukes aren't that big and usually less expensive than other "hobbies" like guitars, or cars.
I will let you know when and if I every reach that mythical number. I figure anything below 3 digits and you are ok, above well.........you might have a problem.
Besides all of the above:
As long as you're still willing and able to sell the lesser used/liked ones you'll probably never have too many.
Remember the old saying "you have to kiss a lot of frogs to find your prince" and keep on searching for your personal ukulele prince.
If you have room for the ukes, can afford them, they don't cause problems with your relationships, and - most importantly- play them, then you don't have too many ukes.
If you find yourself trying to decide between essential things (food, lodging, transportation, taxes, phone) and another ukulele, then you have enough.
If you find you have to sell instruments to get those essentials, then you have too many.
Not long ago, I found myself contemplating a non-ukulele purchase, and when the words "...but I could buy a good ukulele for that much!" came out of my mouth, I knew where my real priorities were...
If you have room for the ukes, can afford them, they don't cause problems with your relationships, and - most importantly- play them, then you don't have too many ukes.
Yes, this. And obviously those factors mean the actual number is different for everybody. My limit is four in terms of space, but for some reason, I only ever have that many if I've bought a new one and am in the process of selling the one I bought it to replace, so - three seems to be my magic number, and four is "too many." My three get played pretty equally, but the times I've had four, I never could figure out how to find the time to play all of them!
In the first year of playing I went through 16, with about 10 at one time, but then I decided to hold onto the ones I liked the most and sell or gift the rest, turned out to be the 4 in my signature. But when I started playing bass uke about a year ago, I now have 8 and seem to have settled down there. (On the Talk Bass forum, people have posted 30-40 basses in their collection.)
I have done a bit of exploring, and have a good number of ukes. I tend to keep the ones that I feel a special connection to... ones that I would regret selling in the long run. Now that I have a little more room, it makes it easier to keep more. I like them as beautiful examples of woodgrain and instrument design, so I don't have to play them all to enjoy them. Someday, down the road, they might be sold or gifted to someone, but for now they are part of my collection hobby. I think it is in our nature to collect. I used to have a small rock collection, and a small foreign coin collection, and a few stamps, and then there are those 50 state quarters....
I think it's like so many things in life - people either are, or are not, without much middle ground, and strong opinions on either side. Some people are collectors, some aren't, just like some people are athletic and some aren't, or some people are good at math and some aren't... and so on.
As I've noted before, I'm firmly in the non-collector camp. Having things in my house that don't get used depresses me, no matter how beautiful they may be to look at, and having any degree at all of clutter makes me absolutely crazy. The only thing I ever tended to collect as a kid was records, and those followed me well into adulthood across three states and some twenty-plus moves until I got tired of hauling them around every time I moved to a new place. Fortunately MP3s came along and - oh wait, I guess I collect those after all
That's easy. If the answer to "how many ukuleles is enough?" is always just one more than I have right now, then the answer to "how many ukuleles is too many?" is two more than I have right now.
In reality, I think if you count the ones you never play, that would be the "too many". Accumulating ukes you never play would likely be considered "hoarding.".................of course that's when it applies to others you understand!
Once I crossed the dozen threshold, I stopped counting, and when asked how many, I simply do not answer. Instead I answer with an uncomfortable (for them) painful question as a distraction, and this usually works well for misdirection.
Those who understand need no explanation, and those that do not will respond badly no matter what their intentions are.
Past experiences have shown me that when they react in horror, or consider me a hoarder, there is no way to redeem myself, so I simply avoid these conversations as much as possible. It is only here on UU that I am comfortable giving hints.
Having said the above, there is some great advice given here by our fellow UU brothers and sisters. Kudos to you all.
, but I also find I like buying new ukes 
