I'm originally a percussionist who picked up bass. Now I'm trying to learn guitar chords so that a) I can look at the guitarists hands and not get so lost and b) I can play along with myself if I feel like singing.
All the instruments are totally different. Out of them......I like playing bass *with a group* the best. Sorry, but bass by yourself in the bedroom gets old after a while (*prepares for flames*

). For playing by yourself in the bedroom, guitar wins... for the simple reason that drums don't go over too well at 2am when you get the itch to play.
If your goal is to play with a group, and you like the way the bass feels, go with bass-you will be in demand and will find a band easily. If you don't like attention, definetly go with the bass. Be prepared to be ignored...... (I had someone ask me, "so, are you the groupie?" and my guitarist said "noooooooo she's the bass player".....duh. You just watched me on stage!!!:scowl:


).
If your goal is to play at open mics and impress your friends, go with guitar. Just be prepared to be a very small fish in a very big puddle for a while. Maybe forever depending on you and the music scene in your area.
One other thing to be prepared for is the effect the economy has on music in some areas..... What I mean is, a lot of places are turning to hiring duos and solo acts for their music. And the instrument of choice for those is guitar or keyboard....not bass. It can get discouraging watching all the guitar players out doing gigs while the bassists and drummers are home....

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What you may also do is make friends with a local bass guy and see if they have (or know someone who has) a bass just sitting around you could borrow for a month just to try it...... maybe give them a deposit or something?
As for equipment, I started out on "cheap" Peavy basses and the furthest I've moved up is to an Ibanez.... you don't have to spend a lot of money to play on a bass. Pick one that feels right to you regardless of the tag. It is a good idea to have a practice amp if you live with other people, my crate BT15 is all I use to play through until I'm with my band. It also comes in handy because it has CD inputs so I can hook my laptop up through it and be able to play along to a song I'm learning.... and at practice I use it as a speaker for my laptop for the band to hear a song. And if the drummer can't make practice, I use it as my amp (the gutiarists are playing acoustic so they just don't plug in).
One last caveat about bass.......the equipment can be very heavy... and a pita to move around. If you have back issues or don't like lugging stuff....... go with guitar

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