Hi,
Just to clear up a couple of things.

There is a difference between recording MIDI and Audio so when you say you want to use a sequencer to record vocals I guess what you really mean is that you are looking for a DAW (Digital Audio WOrkstation). A digital Audio recorder that allows you to capture live audio signal and record it digitally to a hard drive.

A *MIDI* sequencer is not what you would use for recording vocals. It is used to record/play MIDI events. In short, MIDI events are nothing but a set of commands that tell a keyboard to play a certain note (or any given amount of notes) and other MIDI data (controls and so on( using this digital language called M.I.D.I. (Google that one(.

I think if portability and ease of use are a priority for you you are potentially looking at a more or less 'all in one' kind of workstation that has lots of good sounds, MIDI and Audio recording capabilities and of course a good keyboard feel.

To be honest there are no 'all in one ' units that cost little and really work all that great. What you could do is:

1. Get a laptop that's up to specs.
2. A good audio card and a keyboard controller.
3. Some sequencer/audio host application like Cubase, Live, Sonar, Logic, Pro Tools (depending on whether you use a mac OS or Windows XP(.

I know its a little more than just carrying a single keyboard that 'does it all' but to be honest having a computer based setup is by far better option than messing with portable daws and so on. Both Audio and MIDI recording is best done through a computer and software.

I think what you should do in any case is pay a visit to your local music store and find out what is available. Talk to a few sales reps, explain what you need and how much you are willing to spend. From there I'm sure you will be presented with quite a few options to choose from.

cheers,

-ED-