Not sure what I'm looking for (Staples has at least half a dozen categories), but I want something durable and comfortable, preferably around $50 or lower. I don't even know if I need armrests, because it's for home use. I can't figure out the pricing on chairs, so it'd help if I see a discount/sale to let me know I'm getting a good deal, and not paying too much markup.

You can always use a good chair!

In my experience for buying desk chairs for our office, $50 will not get anything decent (meaning supportive, comfortable, high quality).

We have been buying chairs from a local shop that sells used office furnishings. It allows us to buy much higher quality than office supply store stuff at reasonable cost. For example, we bought several Herman Miller Equa chairs with arms (formerly from Yahoo's headquarters before they downsized a couple of years ago) for under $100 each. If you are in the SF Bay Area, the store is Interior Motions in Emeryville (near Pixar campus). New items are also available or can be ordered but the best deals are on the used furniture. I would not consider buying chairs though the likes of Staples, Office Max, etc. again. There is no comparison in quality or comfort.

Well, you can't save with your health. My recommendation would be buy an ergonomic chair. Of course they will not be $50, but they will outlast any $50 chair at least 5 times (I had 2 Office Depot chairs so far, both did not last more than 2 years). If you get high quality used chair it will last longer and you will be more productive.
P.S. I bought a used Herman Miller Aeron, I did not imagined that a chair can make a difference how I sit and how I feel after extended hours of sitting. Highly recommended.

I've had to buy a computer chair several times in the last decade, and the I feel that you will *regret* buying anything under about $100.

The inexpensive/readily-affordable chairs that are commonly available are so flimsy and poorly-designed, it's amazing.

It's not just about poor construction, poor materials, rough handling, and all that. It's about your physical alignment, your mood, your safety (literally - some of the cheap chairs are reported to collapse! check out the chair reviews on the Staples website). So this is not something to scrimp on.

If you are outfitting an office and don't have many funds at first, make a cheap desk out of a piece of plywood and 2 sawhorses or 2 low filing cabinets, and put all your money into the chair.

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My chair search the time before last was in the UK. My last search was in the US. Both times, I ended up buying the very same chair, after looking at many stores and many options. Two years ago, I had to drive 2 hours out of my way when I was on a business trip in order to reach a distant Ikea, so I could buy my current chair.

I really like this chair, and would recommend it, because it is minimalistic, no-fuss, sturdy, durable, and fits in to almost any decor. It's adjustable in 3 ways and has a hydraulic lift. I don't know the Ikea catalog name for it, but it is one of their more expensive desk chairs, about $130 (that price is without armrests, and for the cheapest wool seat-cover color that they had when I was at the store -- which was black in the UK and grey in the US). You can have a snazzier color and add armrests for a bit extra. You can have wheels on it, or not. They sold it for 8 years straight that I know of, but I don't know if they still offer it today. I bet they do, because it was a top seller.

I prefer not having armrests, having wheels, and having a *wool* cover. The wool cover is not hot in the summer - it breathes, and is very durable, does not attract dirt, and is easy to keep clean. Those are personal choices though - go to a few office stores/big department stores and try out the various combinations to see what you like.

Sit a few minutes in each chair you are considering, and take notes because it's hard to keep them straight if you are deciding amongst many options at several stores.

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You could also go to a used furniture store or even a big Goodwill and see what they've got. office chairs, if they are decently made to begin with and have been treated okay, are not too hard to clean up.

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You might also try auctions. Lots of companies are going out of business these days.

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Unfortunately (because it ruined me for any other chair), I had a job where the company bought every employee one of those Hermann Miller Aeron (sp?) $1000 chairs. THAT was a chair you could spend your life in. (Which is what we did at that company, so it made sense for them to splurge on the chairs.)

2 years ago, I found those chairs being sold at some discounts (I think maybe $600 was the lowest I saw), and then there are other brands' knock-offs of those meshy, big chairs that are in the low couple hundreds -- but the knock-offs that I tried were not the same as the real thing.

Check the craigslist. I got mine Herman Miller loaded (all options) for $400. No tears, rips or any damage. I think it was an amazing deal considering they go around $600. I consider it not only a chair, but an investment in my health.

If you buy a brand name as Herman Miller, you can sell it very easy, however, if you will try to sell no name 'leather chair" - it will be either very difficult to do so or it will have almost zero value....