When you buy your first guitar, you should know that they are sold for as little as $70. If you buy a used one, even cheaper. And there is practically no limit at the other end of the wallet. I spotted a Gibson J-250 the other day. $20.000 - a bargain! And the next day I saw a Martin D50 Koa Deluxe practically given away. The price tag: no more than $39.999!
So the decision is all yours. Whether you buy a cheap or expensive guitar doesn'r really matter in the end. A cheap guitar is as good as any to practice on. But I suggest that you leave the very cheapest guitar where they are, unless you are certain that it is good quality. The reason is that you want to get a guitar that stays in tune all over the neck. And that is a problem with a lot of the cheapest guitars.
So I think you need to spend about 250-300 bucks for a classical guitar. A steel-string a little more.
Steel-string acoustic guitar or a classical guitar?
Or...you maybe want an electric guitar? "Nooooo" cries the pundits. But again - the choice is yours. Of course, if you want to study classic guitar the choice is a nylon stringed guitar. But in most cases it is a question of taste. What sound do you like? Make your choice from that.
Nylon string have a smoother sound than the western guitars. They are also a bit nicer to your fingertips. On the other hand they have a neck which is wider than the steel-string guitar. Could be a small trouble if you have very small hands.
As I stated before, you can choose the electric guitar as you begin to play. People have a way of saying "Buy a real guitar" to start with." But the electric guitar is very much a "real" guitar. Its strings are even easier to press down than the nylon strings. You will have to dig a little deeper into your treasure chest, though. The electric guitar doesn't produce so much sound without an amplifier.
Conclusion
So it all comes down to this; As long as the guitar is of decent quality, buy the guitar you want to buy, based upon your likings, style.....and maybe your hands size.
Are you just starting out? Read my 10 Tips to Get You Started in learning how to play the guitar - at Pelles Guitar Stuff!