Okay, I am assuming you are an attorney or banking professional...
Thrift stores are not great for mens business suitable clothes. About once every four trips, I can find ONE shirt of high quality for my XL-Tall DH. I also keep looking for quality outerwear there (it does appear). If you are more of a standard size (not tall), then you may have more luck. No pants, suits, belts, or shoes, however. Instead, use thrift / goodwill for the occasional dress shirt, and your casual clothes to save money.
Buy expensive, long lasting shoes. 2-3 pair, rotate, resole. Same idea with belts and suits - buy one new suit each year, and rotate out the oldest ones.
I think you just need to budget for this expense, and not have too many multiples of things, and save in other areas.
I also use on-line shopping, when I know a specific brand and size fits and is quality. Ebay works great for this. (try it for the shoes, for example, very good results in value for a specific item).