I think everyone tries to coast once... and only once.
In hilly terrain, it's going to take a little bit of time to get the strength and stamina needed to make it up big climbs, but you get the feeling of progress when you notice that you're a little winded after a hill that almost killed you a month ago.
If it's your first fixed and you're relatively knowledgeable about parts and fit, why not go for something used? Esp. if you're looking at something like a Pista that's pretty easy to find on craigslist or whatever...