Downstairs, I have a floating floor of ~1000 sq ft of engineered handscraped 4.75" wide maple saddle floors from home depot and they look fantastic.
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This isnt mine, but it looks a little like this:
I put down some very expensive padding/vapor barrier underneath the wood that I believe makes a noticeable difference.
The den and the playroom have very large and plush area rugs in the middle of the rooms. The playroom has a design that my son uses as roads for his matchbox cars.
I also have 600 sq ft of glazed 16" procelain tile in the kitchen, bathroom, utility room, etc.
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I am absolutely thrilled with both of them.
Upstairs, I am about to put some plush carpeting in the bedrooms, and I have some generic sand tile in the bathrooms, which I also like.
So tile in wet rooms, carpet in bedrooms, and hardwoods w/ rugs in living areas.