Sergers

I need help from anyone who reads this and has serger experience! :) Since I'm going to the states in three weeks, I've been thinking of things I "need" to buy there (like kitschy royal albert tea-cups for my collection that currently consists of 1 tea-cup), and I thought that it might be a good time to buy a serger.

I feel like I'm getting to the point where I might be good enough to sell some of the garments I make on etsy. What I don't feel comfortable with yet are the seam finishes. I zig-zag them but it's just not the same. If someones going to buy a hand-made item from me(that won't necessarily be cheap, since fabric here is expensive), I want them to be happy with it, and I want it to last. And ok, I'd like it even just for sewing for myself. I want nice seam finishes! Plus I might get interested in sewing knits again.

The reason I want to buy one in the states: it's cheaper! Plus the dollar is really weak (when I was a kid I had the formula x dollars is x+ a half x swiss francs (1$=1.50 CHF), and now a dollar is about 0.80 swiss francs!).

I have to admit, I don't know an awful lot about sergers, other than that they can finish seams by cutting and at the same time "wrapping" the seam-allowances in thread, and that the stitches are stretchy, so that one can sew knits with them. And I still need to figure out how I'd get it back home across the atlantic, but the bigger problem is: which one? I've looked at a few online and I'm thinking I shouldn't go for the cheapest (which is what I did when I first got a 90$ sewing machine, it worked fine but I just don't want to risk having to pay more for repairs than for the serger itself), but I can't afford the fanciest ones either.

Does anyone have recommendations (model/brand/type)? What are the important functions for finishing seams? Is it ok to order online or should I look for a store in NYC and try them out? Or are they cheaper in stores in the US? Should I not be scared of the cheapest one (brother on amazon for $200) if I'm going to use it mainly for seam finishes?

I am reading a lot of stuff online about sergers (haha, I have no idea what they're talking about most of the time), but I thought I'd ask here anyway incase someone reads this.