Most people reading this blog probably own way too much "stuff," a problem medieval people did not have. Our many cheap and serviceable possessions are a product of the nineteenth-century Industrial Revolution.
In an earlier post I discussed medieval clothing. Most people in the Middle Ages (and for that matter up through the eighteenth century) would have had two outfits, one to wear and one to wash. Washing of course was reserved until something was good and dirty; none of this tossing it into the washer after one wearing. The overstuffed closets of many of us are only possible because of industrial looms, sewing machines, and cheap overseas labor.
One of the biggest causes of clutter in today's house (looking at my own office as I type) is too much paper. We buy books, we get magazines and catalogues, we get mail, we print out interesting articles, we keep journals, we make notes, we get receipts. This of course was not a problem for medieval people.
Paper didn't really exist; it first appears along the Mediterranean in the thirteenth century, but only became at all common in the fourteenth. Without paper, everything was written on parchment, which requires starting with a sheep and doing a whole lot of processing. Even medieval paper, being rag-based and made by hand, was far more expensive than modern paper, even if cheaper than parchment.
Everything was written by hand until the invention of the printing press in the fifteenth century, and even then most things were handwritten. Books as a result were very expensive, plus you had to know how to read, which left out three-quarters of the population (or more). A good-sized library might have a few dozen books, and this would not be a personal library but one belonging to a church. A hundred books constituted a truly large library. Most medieval books that survive look very well-thumbed, because they were read and re-read. (Click here for more on medieval books.)
Besides clothing and paper, modern "stuff" includes kitchen ware (everything from pots and can openers to plates), furniture, appliances, linens (sheets and towels), decorative objects, cosmetics, window treatments, electronic paraphernalia (computers, phones, etc.), sound recordings, souvenirs, toys, sporting goods, and tools. All of it is good and useful or at least seems like it should be, or could be again. Much of it is imbued with happy memories. We don't realize how much we have until we have to move or otherwise clear out a house.
It's no wonder that one of the biggest selling books right now is about how to make yourself throw away or give away your possessions. Many wish (at least in the abstract) for a simpler set of possessions. Medieval people would also give everything away, but normally only if they were going to go off and be a hermit or something. And they would have had far less to deaccession.
Many a powerful lord's household in the Middle Ages would pack up pretty much everything they owned and take it with them when they traveled. The bed frames would be disassembled, the trestle tables knocked down, the few chairs and cooking pots put on a wagon along with the bedding and the extra clothing, and off they would go. In the late Middle Ages, when the well-to-do got glass for their windows, they would even travel with their glass--after all, you wouldn't want to sleep in a drafty room.