I agree with Mark. In a former life I worked closely with production homebuilders and can tell you that ranch homes are generally less profitable for them as they can put more livable square footage on the same lot with 2 stories and charge more for the house. I wouldn't be afraid to buy a ranch home. Ranches are likely to grow in popularity as the US population continues growing older. Case in point my mom, now in late 60's is looking for a nice ranch to avoid climbing stairs.

The fact the builder does not build many ranch is not a bad sign. It may mean that it is not as popular as a 2 story home but not bad. Most ranch homes don’t have more than 3 bedrooms. Typically the builder will build a 4 bedroom in a 2 story home because they can do so on a smaller lot. A 4 bedroom ranch would be all on one level that may require a larger lot. As far as looking at resale you would have to price an existing home a little below the builder if you have any hopes of trying to sell it. Otherwise why wouldn’t someone just build new and pick out everything they like instead of having to go with what is already in the home.