Most of the time I have the inverse symptom: Buyer's Reluctance.
When I buy computer parts, unless it's an emergency, like a blown PSU or HDD, I start speccing out a configuration about a year or two early. Then keep respeccing it, until the stars align, and I can finally convince myself, that no is the time.
By then I am so focused on those items, that buyer's remorse is impossible. After all, I've been mentally preparing for ownership for years.
At times I feel that some of the cheap items I buy are not up to the task, and that maybe I should've bought something more durable and expensive. But usually I just work around the limitations, and then replace them with something that suits my needs more precisely.
Probably the only thing where I have some buyer's remorse is my wok. But it's not really buyer's remorse, but rather cook's remorse, that I don't find excuses to use it more often. It's a great wok, and every use has been a pure joy, and many meals I like cooking require one. It's just a bit large to cook meals for a single person in. I'm sure it will come in handy some time over the next ten years.