Whatever fits your budget. As long as you stick to one scale for your weight, you'll be fine, because all scales are different. I don't think any scale is dead on correct, except maybe the doctor's scales (but never get upset if that doctor scale says you weigh heavier! You're still losing!)
They have several scales, some as low as $20 and then on up. They have a Health-O-Meter brand on sale for $19 on clearance. They go up to $70. Looks like most of them are digital.
I have a Tanita brand that I bought at Bed Bath & Beyond, but it cost $50. Tells more than just weight, though.
I haven't owned a scale in years, but lots of folks on 3FC said they liked Tanita.
I have a Weight Watchers scale, it measures in .2 pound increments and also measures your body fat percentage, which is nice. I got it on a sale at Kohl's for $25! It's a very nice scale and not too expensive. Good Luck, I Hope you find a good deal!
I have a digital scale and it has weight increments of 0.2 lbs as well. This isn't one of those hot-shot scales that read the body-fat percentage or BMI calculations. I got it for around $30. Unfortunately, its not calibrated and off by .4 lbs.
I have a Weight Watchers scale that has increments of 0.2 lbs. The one I got has a bunch of bells and whistles (body fat composition, water hydration etc.) but I find I only use the weight function. I think I paid $40 for mine but you could probably get one with less functions for less. I also saw one at Costco for something like $30. I know mine is accurate because when I went to the doctors, I came home and weighed myself and both weights were the same.
What scales to buy?
