1. Go to a Men's Warehouse and try on a couple suits to figure out his approx size.
- Most men tend to be between a 40 and 44.
- The jacket should be snug on his shoulders and the correct length (sides can be taken in by a tailor later)
- Make sure to note R (regular) S (short) or L (long) for jacket length.
2. If your budget is really only $300-$400 then Suit Supply is probably your only good option (if in or around NYC, Chicago, or DC skip 1. and visit a Suit Supply store)
- Choose a suit style from here -->: http://us.suitsupply.com/suits/Suits,en_US,sc.html
- The "Washington" is the slimmest/most modern style so if he isn't in above average shape try something like the "Napoli" or "London" model.
- If choosing the "Washington" try buying the suit size you determined earlier and also 1 size up in probably a Short aka get a 40R and a 42S and mail back the worse one.
- If "Napoli" or "London" buy the suit size you determined earlier and buy the R and L just in case and mail back the worse one.
- If you want to decrease the width of the waist portion to make the suit look better or increase the V shape, take suit to a tailor and ask for the waist to be "taken in".
*This is by no means a complete or perfect guide as such would take too much space, but following this will yield a well enough fitting suit at a reasonable price quickly.