It's only $499 USD so purchasing is no problem.
It's only £395 GBP here in the UK, so I'm going get one myself quite soon.
Now to decide if it would be one of those spur of the moment buys that winds up gathering dust or if I will really learn to play the thing.
Well, before buying, ask yourself if you're going persist with it. Like, really persist with it. Because those early stages of learning how to play are what's going to determine whether or not it'll be a spur of the purchase that ends up sitting around collecting dust. Because it's quite frustrating at times, initially. There's going to times where you'll feel like quitting early on, especially when you're learning the chords, but aren't getting all the notes to ring out. Not saying all that to put you off or anything, just speaking from my own experience.
Long story short: having a defeatist attitude as soon as run into difficult won't help you progress to a point where you get good. Stick with it and you hear your playing improve in over weeks and months. Depending upon how often you practice, of course.
My brother is quite a good guitar player so I'd love to learn, myself.
Much like you, I had a couple of family members who played the guitar, and taught me the basics in terms of chords. Though they gave up on learning how to play after while and never really progressed. Whereas I kept at it and got pretty good.
So, maybe, you could ask your brother if he'll teach you how to play the guitar?
No problem!