Everyone should have at least 1 or 2 of these in their closets. It's not an option, it's a must have. Why? Because you can't dress up without one.
What separates one well dress man from another is not how expensive the clothes are but how well they put theirs outfits together and how good the fitting is.
This item is an investment you should not hesitate to purchase. It needs to fit you perfectly or it will not work. If you are on budget but found one on sale but its arms length is a bit too long or waist is a bit loose, buy it and get it to alteration places near you to make some adjustment.
A good sports jacket will make you look well groom, make you look like you do care about yourself and how you look, hides problems where T-Shirts or knitted garments will not be able to do for you.
Colors of sports jacket that you need to have in your closet:
GREY or BLACK
You should have at least one of each colors from Springs and Summer, which comes in lighter fabrics. You can even choose linen fabrics for the brown color. Then you need three more of these jackets for Fall and Winter, but I would make sure there are more room around the waist and under arms for layering clothes. I normally would go for a size larger but same length for Fall and Winter.
I personally preferred single breast rather than double breast jacket, it'll make you look more slim and 2 buttons instead of 3 buttons jackets.
Once you got these down, then you can explore more options in terms of colors, pattern or prints. I would start right away in the same color tones with plaids or houndstooth patterns before I would purchase other solid colors. Because, color tones changes from season to season but plaid sand the first 3 colors are classics in menswear. Safe your money and buy printed shirts instead of printed jacket.
After you got all these down, you are free to purchase cheaper version jackets or some seasonal sports jackets that you can have fun with, like polka dots, pastels colors, or even prints, they will become your novelty jackets. THE KEY IS TO MAKE SURE THEY FIT YOU PROPERLY.