Parents say no, brain says yes. Advice?

As a parent who likes to say "Yes" whenever possible, I'd have to say that you need to present some basis ;) for this purchase.  If you already play guitar or other instrument, do you practice consistently?  If not, then why get something else that you'll ignore after a month or two?  Alternately, consider renting for a while to see if you'll really make a go of it.  However, if you're a good musician already, then learning/owning another instrument is good for your music career.

Is there an existing or potential band that needs a bass player?  If not, then why the bass?  It's not really a "by yourself" instrument.

Good Luck!
Laz

Yeah, Laz said pretty much everything there you need to know for your decision.  Especially if it is your parents money or came directly from them.  Even If it's your money earned from a job, If they are having financial dificulties, they may be reluctant to let you spend that money on soemthing they consider frivolous.  But, hey, I am all for you getting that bass.  When you get it, let me know and I'll go by that other bass I've been looking at that I don't really need, but want.

I remember reading an article a few months ago, I believe by John Tucker, about necessity.  If you want to buy the bass just because you want to be able to say you have a bass, then you aren't buying for the right reason and your parents might me justified.  But if you are really looking to expand your horizons I would say bass is a great thing to learn (it was fairly painless for me) and as long as you are paying with your own money, I would advise you to continue to attempt to convince your parents of the merits of buying a bass.  Perhaps buying one against your parents will isn't the smartest thing to do, but when push comes to shove maybe it must be done.
Good luck and rock on

Well it's a glory of what can come of a nights sleep. I thought 'Nah, I don't need a bass. Heck, I don't even play guitar. I'll get a cheap acoustic, start to play and hopefully show my parents I'm interested' maybe then I transfer over to bass. It's a very need vs want type of thing. A friend recently purchased an electric guitar so I guess it's just either

a) Envy
b) Stupidity.

Who knows? I may be graced during my birthday time with a bass :)

That's a really really good idea.  I think it's a good thing to get a general feel for the guitar and see where you want to go with it before you try bass, so investing in a bass guitar now would probably be a mistake.  
Go with the acoustic and see if you just generally love playing.  I started on 6-string electric guitar and have recently picked up the bass and I think I have been able to pick it up quicker and get more gratifying results because I already have an understanding of how it's going to fit into the melody etc of other guitars.  
If you eventually get a bass, it will be much easier to play if you have a bit of grounding in general guitar playing AND playing the bass will also improve your playing on the 6-string guitar....either way, you can't lose!
Good luck! ;D
xx

Question is..if I can find a cheapish 100 odd dollar acoustic guitar, should I buy it? After all I'm not exactly going to be blasting out mega-hits on it.. I'd just want it for practice. Is it right to buy a cheap guitar?

Buy used at that price or rent a guitar from the local shoppe.  That way you'll get a better guitar.

@ - Deaky,  If you don't even play an instument, yet, lessons are definitely in order for whatever instrument you choose.  One good thing about starting on an acoustic and taking lessons there is it will get you in better shape for playing bass.  A bass usually has wider frets and and a wider neck and it is harder to press down on the strings due to the thickness.  An acoustic guitar sometimes has wider frets, a wider neck and the action can be higher unless you are talking about a higher end acoustic.  Make sure you get those lessons though.

I wouldn't have thought you'd have to pay $100 for an acoustic, could probably find one for much less....check out classified ads and second hand areas of guitar shops, as someone suggested.  

Whatever you buy, just have a go on it first (holding it, press down the strings etc) and see if it feels right for you.  I think to start with it doesn't really matter how the guitar sounds too much, just so long as you're comfortable playing it.  

:)

Right - I think ShinyPinkGuitar summarized my long winded speel very nicely.  If it feels right, go for it!  Do you agree, SPG?

Yep, exactamundo!  And lessons (as suggested by 97reb  ;)) are a great idea - the money you saved by buying a cheap acoustic instead of an electric bass plus amp can be put towards a couple of lessons to give you a start.  

PLUS, by booking some lessons you'll prove to your parents how "keen" and "committed" you are to learning - they'll love it!  Before long, they'll be showering you in guitar-related gifts hehe  ;D

x

Then, as SPG would probably agree, once you get the folks on your side...  The bass is there.  
Keep that bass in your thoughts, even if you are taking acoustic lessons.  Bass players are usually in demand (so are drummers).  Everybody plays guitar.  Play a little bass, so if the opportunity avails, go for it.    Play some keys and learn to sing, keep your options open and then you can do more.

Wow, they're all valid reasons and I've come to the conclusion to get a junkety old acoustic, stick with that and if there's some question 'round Christmas time like 'What do you want for Christmas?' well.... I think I've got a pretty reasonable answer. :)

Thanks :)

Well I managed to snare a $10 Suzuki guitar...looks reasonably old. It had a string missing (the D string, from what I can gather) but I went to the local guitar shop and got it re-strung and serviced. Looks quite good now and so far I've been just plucking at it...I've taught myself a crude version of the bass start of Another One Bites the Dust, Smoke on the Water and Hot Cross Buns (which is rather appropriate at this time)