First, I look for what fits me well, as not all brands do, then they have to be within my price range. And it definitely has to be a brand I like.
I like to look for good deals, and I have never payed over 40 for jeans.
In the past 6 months, I've gotten relaxed straight Levi's for 15 and 20 dollars (501s are uncomfortable on me ), straight and boot cut Express jeans for 22 and 33 dollars, and some Ben Sherman straight leg jeans that fit me very well for 34.
Another of my favorite that fit me well are J. Crew, but it's more of a hassle to find those under 40.
Also, I don't really understand why any guys would wear skinny jeans. Looks weird to me, along with very uncomfortable.