In my experience, most quality furniture that is specifically designed for artists tends to be VERY expensive. Even the simplest of art carts can often run several hundred dollars. This is due to the fact that it's a relatively niche market, and low production numbers means high costs. I can appreciate quality workmanship and am willing to pay extra for it (literally all of my studio furniture is solid oak), but whenever I browse the furniture at an art store, I always feel let down. The quality of the product rarely warrants the exorbitant costs, in my opinion.
Take for example this very simple Dick Blick taboret. Now, I love Dick Blick, are I can personal attest to the quality of their furniture, but I can not fathom what artist would think that this piece of furniture is actually worth the MSRP of $659?!
This Dick Blick taboret is currently 50% off, and is still $316! (MSRP $659)
If you're looking for a new piece of studio equipment, there are quite a few unconventional options you should consider before you purchase something at an art store. Many of these options are of lower cost, and of higher quality than more traditional artist's furniture. Not all of them are pretty, but most are built to stand up to serious abuse and are much easier to clean.
I found all of these products on Amazon, but once you know what you're looking for, I suspect local hardware and automotive stores may actually be an easier and less expensive option.
This is a very common kitchen cart. You can find these at just about any Walmart or Target store. They are very inexpensive, and make wonderful taborets. I like that they have a paper towel holder, making it easy to reach for a rag when working. There is a also a large compartment spacious enough for unsightly trash cans. For the money, I think this is one of the most cost effective options for studio equipment.
Here is a Portable Tool Tray (used often in automotive work). This would make a wonderful taboret to keep next to your easel. You could place a sheet of glass on the work surface to make a palette, and the adjustable height makes it convenient for both standing and sitting work.
Here is piece of equipment I've seen a lot of artists use as a taboret, including Paolo Rivera. These rolling tool chests usually consist of 2 parts, a large bottom half, and stackable top half with a lid. I like this version because it is a single piece and MUCH shorter that more tool chests, which makes it more practical to mix paint on. This option also has the useful feature of a lid. This means you could mix large amounts of paint, and simply close the lid when you're done, preventing the paint from drying too quickly or collecting dust.
Here is a slightly larger version of tool chest above. In addition to having more storage and an extra work surface on top, It also has a socket/screwdriver holder on the side that I bet would hold paintbrushes quite well!
This storage/work table definitely isn't cheap, but man is it beautiful! It's actually marketed as both a workshop table, and a kitchen cart. Like most of the options I've shared here, the entire body is stainless steel and all the drawers are on glides. The butcher block top is both durable and classy. And even though $700 may seem expensive, I challenge you to find a similar sized 'artist's' workbench for less than a $1000.
Industrial options doesn't just extend to furniture. Even simple things like rags, large brushes and color balanced light bulbs are much less expensive to buy at your local hardware store than they are the hobby shop. So look around, try to find unique solutions to your studio problems, or consider making your own!