I think it's nice to own one perfect suit. You will wear it to weddings, funerals, and job interviews if nowhere else. But one can get away without a suit. In our Texas cities, no one wears a suit every day to work except lawyers or politicians. The blue blazer is the true staple to a man's wardrobe. In a more practical sense, I didn't scrimp and bought a very expensive blue blazer, which can be correctly worn with a tie and gray worsted wool dress pants in place of a suit. It can also be worn casually with a t-shirt and jeans. The matching coat and pants of a suit looks a little stuffy; while with the blazer, you can add a different-colored waistcoat and different-colored pants that will look much better and less formal (while still being dressy).
A tailored suit correctly made of worsted wool and lined in silk should typically cost anywhere between $500 and $1,200.