Having completed about 500 sq ft on my own solid hardwood flooring project, I just thought it might be useful to generate a top 10 mistakes list.
I'm thinkg about 3 catagories. Material selection (e.g. strip, plank, species...), preparation, and installation. Here's my list so far:

Selection: 1) look ended up be too dark after installation

Preparation: 1) Didn't get subfloor flat

Installation: 1) Didn't close gaps enough when nailing 2) When nailing, tongue split slightly on some stips and left these in anyway. Now it seems like they crack when walked on...