I agree with Ziggy; style is very important. If I don't like their work, I'm not buying from them.
As a buyer of visual art, my personal preference leans toward realism. It doesn't have to look like a photograph, but a style that leans toward that attention to detail is what I like best. I do buy other works, though I'm ignorant of the visual differences between expressionism, and cubism, and [?]ism, and . . . Though I am poor, mostly by choice, I'm willing to spend rather large sums for quality artworks that I want.
Something else I like in an artist; a sense of professionalism. As a one-time business owner (successful, but ultimately too stressful for me), I understand the importance of establishing and maintaining contact with one's clients, and keeping one's word to them. The majority of artists that I have contacted over recent years have answered my request(s) with "No reply". Though, as an older person, it has been hard for me to accept that "No reply" is the younger generations' way of saying, "Not interested. Don't bother me," I'm doing my best to learn to accept this recent social/business dynamic.
One thing for certain, if an artist ignores my message/request, I will move on. A few days to a week of silence is fine, but if that artist's first contact comes weeks or months later, assumedly because they are now ready to take on more work, I invariably tell them, "Sorry, but I've moved on to someone else." When the artist contacts me weeks or months later, the initial 'no reply' answer makes me feel that I may not be able to rely on them to actually do the work. To me, it certainly doesn't feel professional. This is not impatience on my part; I have waited as long as 17 months for a work from an artist that I liked. That artist made contact with me right away, and maintained contact throughout the wait. I paid $600 for that work, and am still very pleased with it.
I guess those are the most important qualities that I look for, when commissioning an artwork.
