Sizing is often my issue as well, except that it's usually more about either "outdated" cuts (baggy where now more tailored/fitted is fashionable) or where decent looking stuff in my fairly average size is often snagged, leaving only the very small or very large sizes behind.

Still, I occasionally find some decent stuff and I still hit up the Goodwill anytime I'm out running errands and pass near one. It's just a matter of luck so the more often I look, the better my odds.

I tend to have less luck with the common stuff like nice wool pants or well-fitting button down shirts but I've gotten some really nice jackets and at three pairs of Allen Edmonds shoes ($250-350 MSRP) for $20-25 each with only a cleanup and polish needed.

It's nice because even though I'm still buying the occasional $20-40 shirt, I've got a few pairs of shoes that are much nicer than anything I'd be able to justify buying at retail.

Large is pretty standard size for tall men. Pretty much required over 5'11.

Yeah it is lucky. I have a odd body type, I'm 6'3" but only weight 170 pounds, so I really wear a XL-Tall but a lot of the XL clothing works pretty well. It's also a hit or miss every time I go in. Sometimes I will find 10 things that fit and are great, other times I leave empty handed.

Buy the big sizes then get the shirts tailored to fit for roughly $20-$25. You'll be wearing nice brands that fit perfectly.