Now I'll (always) need one more

The eternal trouble with collecting: we first bought one Scheurich vase from around the late 60's. Then we found one more. As a really good vignette needs odd numbers, we started to search for one more. Well, we found one...but then we found another one and now we have four and would need a fifth to make the vignette look good again. As these vases are rather cheap and I just love them, it was not an option not to buy the fourth one. Just guess, what'll happen right after I'll find the fifth one...well, the more the merrier.