I've been doing pretty good lately, but I've been mostly sticking to the tried-and-true. Brands that always fit, or replacements. For example I just rec'd a replacement VC striped tube skirt I saw on Rack for a song... and no surprise, it fits, because it's identical to the one-that-pilled-eventually (like Velveteen Rabbit it eventually became real, I guess!). I also ordered some replacement midi dresses from ON in a style I lived in round the clock last summer, and yep, they fit too. I love ON for summer basics, I refresh every year about this time.
I did just mail back 4 items today: 1) a WHBM leather jacket size SP, after ordering and waiting patiently for a MP to compare. The SP was oh-so-close but on the tight side; I had a hunch the MP would fit perfectly, and it does. 2) ankle straight trousers from WHBM; I'd ordered both 4p and 6p to compare (at same time I ordered the MP leather jacket, because I knew I'd be returning anyway -- I do that a lot); I can now tell you I'm a 6p in that brand and I will probably be trying out more pants; 3 & 4) my two purchases from Nordstrom's sale, both Angie pics. They were nice and fit, but once I got them, I realized I had major sales goggles on and don't really need either one... as I have a long list of other essential things I *do* need right now....
Today I ordered those Clarks cloud steppers I passed up this weekend in the store, and while I was at it, a pair of Asics Metrolytes. There's a good chance the Asics will work for me, as that is the only running shoe I've worn for 25 years.
Also I think I will sometimes keep "good enough" things just because it's a pain to return. I fear I'm far more pickier in the store, than at home.