buy a nice single-speed on bikesdirect
Yeah, get a bicycle if you're thinking about travelling. I'll write a serious reply because I don't really value my time or rep.
Personally, I think longboards are stupid, as for every downhill rider going as fast as a car and risking death, and every dancer doing something creative and flowy on the board, there are a thousand dipshits pushing mongo in flip-flops while texting, swerving into rush-hour traffic at a glacial pace of one languid push per minute, then, once their playtime is done, dragging their 10-foot-long surfboard on wheels through the trucks around like a caveman, all thinking that they're the coolest people in the world for having bought an oversized version of a toy.
If your goals are limited to going back and forth on a board as long as a Cadillac up and down your street, perhaps pulled around by your dog, then by all means get one and pat yourself on the back. On a skateboard, you'll have a steeper learning curve, but much greater chances for technical progression, not to mention the fun you'll have -- or expect to have. Maybe I just don't "get" longboards, but here's my opinion and hopefully it will be useful to you.
If you feel lured by the magical world of longboarding and you're on a budget, I recommend you to just buy a regular skateboard, and get a set of softer, bigger wheels too, and the appropriate set of riser pads to install them. This way, you'll have an easy, smooth ride while still not depriving yourself of being able to go up a curb. I'm sure it's cheaper, too.