I've got a 75 gallon saltwater setup that's been healthy for the last 5 years it's been up. Saltwater tanks are no harder to keep up than a freshwater tank. Supplies cost a little more because of the salt you need to buy. Jack's usually has it on sale every other month for buy one, get one free. Byerleys is the best place to go by far. Aquarium Adventures has some cool fish but expect to pay almost double for a fish there. Jack's has a bad rep for poor water quality. IMO If you think you want a saltwater tank then do Saltwater. No reason to fool around with freshwater for 6 months just to drain it and set it back up with salt. If you do go salt, definitly get a good canister filter, a protien skimmer, and good lights perferrably a 2 bulb ballast with an attinic blue bulb and a 10-20K or full spectrum bulb. Everything I said is for a "Fish only" tank. If you want to talk reef, well that takes a little more upkeep. I wouldn't reccommend a reef tank for a beginner.
good luck