When I got my first scanner, I didn't R E A L L Y need one...... but I saw one for like $50. So I got it. Worked great for a while... Anyhow, point I'm trying to make is you get what you pay for. Don't get the cheapest one. I have an HP now.
Printers seem to last me 4 or 5 years. Don't know if this is good. I like the ones with several ink cartridges, so you only replace the color thats out. Mine's a Canon.
We have an Epson ink jet / scanner / fax that's a few years old and still works fine. I like to buy that kind of equipment at Costco because you have 6 months to return computers etc. for any reason, even if you a better model came out and you're trading up.
I have a HP Photosmart 2710 all-in-one thats about a year old. Its the first WiFi one I have seen. I bought it at Best Buys, they have replaced a couple of other ones I had problems with with no questions asked.