Plenty of free advice for beginners:

1.Determine what you really, really, want and hold out for it.
2. Avoid shipping costs.
3. Network.
4. Read to learn.
5. Buying your first donor bike feels dirty. You will get over it.
6. If it's not your size but a good deal, pick it up (see 3).
7. Avoid Ebay fee's (see 3).
8. Aviod repaints.
9. Google is your friend.
10. Make sure it fits (see 1).
11 Trade up.
12 Have fun.

And since this is supposed to be a visual. As stated above, quality of craft matters certainly, but there are many other variables.

I would argue that the bike with the crappiest welds in my garage is one of my most expensive, sought after and collectable pieces.

Supply, demand, provenance, etc..