Purchase without knowing value? That's the easy part.
1. I see it
2. I love it and gotta' have it
3. I can afford it
4. I buy it
Because I pay attention to step #3 I've done okay most of my life - some stuff finally increased in value over time - but the important thing was step #2. I buy for enjoyment of the item and not as an investment.
This is what happens to those of us who collect "stuff". It's fun. KB