THINGS TO REMEMBER:
Solid wood floors get pricey based on the width of the planks, wood species and any special treatments (hands-craping, distressing, etc.).
Planks must be nailed to a sub-floor, increasing the cost of installation and making them unsuitable for use directly over concrete.
Changes in humidity can lead to squeaking and buckling. This sensitivity to moisture rules out wood floor installation in basements and most bathrooms.