All good advice above. ( I say this as someone who was in Nickhere's position a couple of years ago!) Let me add to the mix:

Don't bother with the "Rogue" model that Musician's Friend sells online (totally different from the Breedlove Rogue). The Musician's Friend instrument is cheap for a reason! The quality is uneven and there is not good bracing inside it. I received one as a present, and the top slowly collapsed over 18 months of light playing.

Definitely try to find a used version of an instrument that would have a "mid-range" price if purchased new, even if the used's price is a bit higher than you anticipated spending. If you decide you don't want to pursue learning to play it, it will be easier to resell than a cheaply-made instrument.

Think about the style you want, since different styles will have different sounds. The "celtic" mandolin mentioned above will have a round or oval soundhole and a "barking" sort of sound. Bluegrass players favor the F-style mandos; they have a strength of tone that will not be drowned out by a mere couple of guitars -- these things are made to compete with banjos for your ear's attention! The A-style mando with F-holes is somewhere in between in tone (more sweet and less shrill than an F-style, less barky than a celtic), and it tends to be less expensive than the F-style. Roundback or "potato bug" mandolins are great for Middle Eastern music but they're difficult to hold unless you're sitting cross-legged on the floor!

Do you have a friend or relative who might be persuaded to lend his/her mandolin to you for a trial run to see if you enjoy playing it, before you make the commitment to purchase one of your own?