(Daily Finance) — Why pay $649 for a new cell phone when you can get it for one-third of the cost? Slashing the price is just a matter of signing on the dotted line: All you have to do to earn that hefty up-front discount is stay true to a particular cellular plan for a while. But what do youreallyget for your money in these shotgun weddings? Is a two-year contract really a fair trade for the discounts you’re getting? Like most relationships, it’s complicated. Sometimes you come out ahead in terms of penny-pinching with monthly prepaid deals and sometimes you don’t. But one thing is almost always true: The phone companies are indeed after your money. But you shouldn’t just hand over your wallet without knowing what kind of plan you’re getting. Here’s some background info on some plans you may be considering. Do your homework and the perfect deal is out there, somewhere.