Time and attention cannot be replaced; a day cannot be redone. On the other hand, you can earn more money. So it is a false equivalence that "time is money"—as the saying goes "money can't buy you more time". Time and attention well spent will continue to pay you (e.g. if you have cultivated virtues, built up good relationships). However, lots of money made and spent today might leave you no different (or worse) tomorrow; imagine earning a $150k/year salary in some high tech job and you have a proportionally scaling luxurious lifestyle... ...and then you get laid off. Having bet your lifestyle on some "guaranteed" income where do you then find yourself?

If you had spent your time/attention doing useful things like developing strong attention, learning generally useful technologies, and so on and so forth, then this discipline will continue to pay you. However, if you landed some position as a grifter and really didn't learn anything... well now all you have is burnt time.

"There is no such thing as a free lunch"

Doing some (residence) moving has been educational.

Getting items for "free" has a heavy price. When we take on additional possessions (or hobbies/interests for that matter), we not only need more physical space, but we also give up the time that is needed to manage these things.

As previously mentioned here, I've done some buying and selling on Facebook marketplace. This will make you appreciate (normal) stores for their convenience—buying or selling things can involve a lengthy process of figuring out logistics, buyers/sellers flaking, etc. So what may have sounded like a $40 "profit" may end up being an hour of time spent over a fews days dealing with the listing(s), communications, etc. That being said, if you accept a bunch of stuff for free and then intend to go sell it, you may end up spending a lot of time doing so. Of course if you could afford to pay someone to do Facebook marketplace for you full-time, I think you could effectively use it to clear out lots of items and maybe even make some decent money. However, for most people that just have too much stuff, you find yourself with a much bigger time sink than say... having an estate/garage sale for a day.

One way to avoid lots of complication is to stay focused, acquire things that are useful and/or easy to resell or give away, and to avoid "novelty" items, cheap decorations, etc. Rather than buying a (fake) plastic plant, why not just keep a nice (real) house plant? If you really gotta purge a house plant, you return the plant to the earth—humans have been doing this for as long as they've been around. You can avoid dumpsters/pollution/trouble...

"Out of sight, out of mind."

Introducing complication to your life means more time spent sorting through your confusion.

Not seeing what is happening doesn't mean that it is not happening. For instance, many people think it is somehow virtuous to do more cooking than eating out. Now, certainly learning some cooking is a useful thing to do... however, to elevate cooking too much is not good. Without a proper kitchen, proper cooking can be very difficult. But I don't think it would be right for you to try to build out a really fancy kitchen for an occasional homecooked meal so you could say to yourself "aha! I'm a responsible adult". Better is to learn some simple, effective cooking with minimal supplies and save more complicated cooking for when you have access to a more complete kitchen.

Americans try to do a lot of things at home. For instance, many people buy lots of expensive exercise equipment. This is fine if you use it frequently; you can have a very nice setup this way. However, for many people (e.g. those dwelling in small-ish apartments), it makes more sense to make use of a gym, the outdoors, or even friends' equipment (with their permission of course) rather than dishing out the extra dollars for more stuff that takes up more space.

Payment

People give you money in order to sove problems for them. Although "free stuff" may sound like you are getting a really good deal, maybe more of what is going on is kind of the opposite—sometimes I may agree to take on some burden—e.g. accept an item from a family member which I really don't want effectively so that family member cannot "feel bad" about "throwing something away". But what often happens is that the issue of extra item ABC is pushed onto me* and that thing is "out of sight, out of mind" for the giver.The gift is to the giver.

This isn't to say that we shouldn't give things away; rather when we get things "for free" we should consider what we are going to do with the items we get and be willing to say "no" when we are unwilling or unable to shoulder some additional burden.

It is better to prevent problems than to have to work through and correct them (which takes more time, energy); so if you can avoid buying stuff you'll have to "get rid of" (e.g. some rando "gift item") then this takes away the "should I throw it away?" burden from yourself or another person. On the other hand, gifts like flowers, food items, etc (I call these "consumable") more intuitively have a short "lifespan".