That's my problem. The art I buy, I like, but it's never worth much. lol.
As far as buying goes, if it's only a couple dollars and it won't break you then I say buy it. Of course if your like me you'll end up with a couple storage units, a workroom/shed and a spare bedroom and closets full of boxes of stuff. Not to mention the display cabinets that are stuffed and overfilled. It's all good sellable stuff, but it adds up quick if you don't commit the time to selling it. Your house will start looking like Hector the junk collector's, if your not careful. I'm glad the wife (tries and for the most part does) keeps me in check.
Anyway, for a few dollars it's not much of a risk financially, so go for it. You can always resell it for an extra dollar or two at your own garage/yard sale if turns out to be not worth selling online or whatever. One word of caution though, when it comes to art, more specifically paintings, take into consideration the size of the picture and what it will entail when trying to ship it as far as packing goes. Large paintings can be costly to pack/ship. I have one now i'd like to list but i'm not too sure how to pack a 36" x 48" glass fronted picture frame securely, so it hangs on my wall instead.
Good luck!