Here are my top five tips for buying your first guitar
1. You get what you pay for (up to a point)
The first guitar that I ever got was a second hand acoustic that my Dad bought from a pawn shop. It probably cost the equivalent of £100 and the the "action" was so high that it was impossible to play any notes beyond the fifth fret. Within a few weeks, one of the tuning pegs had come off.
It was a horrible thing and eventually would have limited my progression as it was so tough to play.
The second guitar I got was around the equivalent of £300. It was a Fender Strat rip off, but it sounded fine, the "action" was low enough that I could play some solos and I enjoyed having it for years.
With guitars, I think you will struggle to buy a decent guitar for less than £130, so I would set a budget for a beginner's guitar around this mark. Remember though, if you're buying an electric guitar you will need to buy an amp as well.
If you want to spend more than that, and hey it's your money, I have found that from £50 to £130 there is a massive jump in quality. From £130 to £750 there is another jump in quality (although less noticable) and from £750 to around £1500 another jump (but even smaller than the last jump). If you have more than £1,500 to spend on a beginners guitar, I'm very, very jealous (can I borrow it?!).
2. Buy something from a reputable brand
There are many different types of guitars and there are even more brands.
For your first guitar, I would stick with a known brand; e.g.. something
like Fender (or their economy brand Squire), Gibson (or their economy
brand Epiphone), Martin, Yamaha, LTD or PRS. Basically avoid a brand
that is not stocked in major retailers.
With a big brand, they have more to lose to the company's reputation
by churning out an unplayable guitar.
3. Know what you want to do with it
Each type of guitar (e.g. classical, acoustic, hollowbody, electric)
produces a different type of sound and serves a different purpose.
Some are more obvious, that is a classical guitar is suited for classical
and Spanish music, but within electric guitars it gets more tricky. For
example, a guitar with a "humbucker" pickup has a heavier sound and
is better suited to heavy rock/metal than an electric guitar that has
a single coil pickup. A single coil pickup generally has a twangier type of
sound and may be better for blues or country.
Work out what kind of sound you want and then do some research into what you can get that best suits that style.
4. Read articles (but take them with a grain of salt)
There are a lot of products out there that guitar manufacturers are trying to sell you.
Getting a good, playable guitar is absolutely critical, and there are loads of unbiased reviews that can help you find online. Obviously Amazon is a good choice for reviews.
I have been asked in the past by beginners about how much they should spend on a battery for a pedal, a guitar pick or a guitar cable because they read online how their favourite guitarist mentioned how critical this product was for their sound. With things like that you need to just use your common sense. For a world famous virtuoso guitarist the best guitar cable will make a 0.01% difference to their sound compared to an average cable (i.e. for an audience member completely indiscernible). For a beginner who is learning to play their first songs, it will make no difference. Of course, if you buy a cable from China for 50p and you can't get a sound at all out it, that will make a tremendous difference!
Obviously, it is nice to buy stuff and great when the package arrives on your doorstep, but prioritise what you need.
5. Ask someone who knows
As far as I can tell everyone has at least one mate who plays the guitar fairly seriously. So, ask them for their advice or go over and play on their gear.
Otherwise just go along to your first guitar lesson without a guitar and ask your guitar teacher. If they can't tell a classical guitar from a Fender Strat, I would avoid block booking lessons in advance!
Here are some explanations
Action - is the distance between the strings and the fretboard. If the action is too high it makes playing almost impossible. If you turn a guitar side on, you can quite easily check to see if the distance is consistent.
Me and my first electric guitar - 1995
That look says "take the photo, and leave immediately"