You don't need an FCC certification in the U.S. as far as I know. If it's a commercial device to be sold in bulk, then you probably will, I'm not sure. I've got 10 different 'things' I've built running around the house/yard/garage, I don't have any certifications, then again, I live out in the sticks.

Range...
Well, it varies wildly. The best I've gotten is about 1/4 mile on 12v on the Tx at about 9600 baud (4800 if you use manchester encoding), big tuned antenna at both ends, etc. Generally, I can easily get about 100-200 feet on 5v on the Tx, 12-15 wire antennas at both ends at 2400 baud.

JDG