What tricks help you buy smarter?

[Jeremypat]

This might be a little off-topic
 
Just not long ago I found a site called resource for wise buyers.
 
They share great tips like:
- how to read product ingredients,
- checking expiration dates properly,
- not overpaying just for brand names.
 
Clear, practical, no fluff.
 
Thoughts on shopping smarter like that?