A leads to B leads to C leads to D.
(A) My faucet-mounted water filter needs to be replaced. I don't have any new filters and would need to buy more, and the Pur filter holder is wearing out. I figure that I'll just order a new one for about $30.
(B) I start looking at new water filter holders. Reviews for the one that I own are pretty bad, and while mine has held up for a while, my experience with Pur faucet filters is that they start leaking after about a year (I'm on my fifth one). Plus, I have trouble washing pots and pans because the filter moves the nozzle down pretty low into the sink. So, I start looking at under-sink filters. The ones listed as being for "drinking" water use a separate little faucet. I don't have a spare hole for a faucet, but I have a hole where my sprayer handle is.
(C) I like my sprayer and don't want to loose it to add a filter faucet. Some new kitchen faucets have built-in sprayers, though, so I could remove the separate sprayer and put in a filter faucet. Hmmm.
(D) I just ordered a new kitchen faucet (with sprayer) and an under-sink water filtration system for about $315. During my search yesterday, I ordered a $60 shower filter.
So, $30 turned into $375. Oh, well. I sure hope that the new hardware fits. I'm also cleaning my kitchen sink, as it is nasty. I'm on my fourth application of CLR, and whatever the heck is on there is holding strong...but I'm starting to see kinks in the armor.