1) Yes
2) Not on it's own but you can setup a FTP site on one of your computers and point the home dir to your NAS.
3) I have been looking for a NAS solution for my place for awhile and haven't exactly found it. My budget is around 100-150 and you can get a few good models for that price range. Just make sure you read the reviews. Speed is usually the big pitfall for the lower priced NAS solutions.
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