Garages are commonly available in three types, which are concrete, metal and wood.
Whilst a concrete garage may seem the obvious choice for many people, as it does offer a high level of security with the only vulnerable points being the flat roof and the main door (as then the other two options), as the walls are very solid, it also has several disadvantages over a timber garage.
Firstly it is going to be a permanent structure and as such may need planning permission depending on where you live and sometimes, how close it will be located to nearby buildings. Timber garages are in the main not classed as permanent structures and so avoid this issue.
Whilst for all three types of garage you will need to put down a concrete base to take the weight of your vehicle as well as providing a level area to put the garage on, with a concrete garage you may have additional foundations to dig to take the weight of the walls, whereas a steel or timber garage can simply be identified on the cars concrete base, without the need for further foundations.
When it comes to aesthetics then a timber garage wins hands down as both concrete and steel ones can look fairly obtrusive. Whilst both of the others can also be painted, they are both likely to need repainting a lot more often than wood, particularly a metal garage, which may need all the old paint stripping off before repainting, as it will flake off with age.
A timber garage can be painted or stained just about any color you want, and will not need doing yearly.
A timber one is also easy to erect over a weekend with a little help, or pay for the installation from the supplier and it will be ready to use by the evening of the day it is delivered.
Timber garages can also easily double up as workshops and due to wood being an insulator they will be warmer inside in Winter. Power and lighting can easily be installed without the fear of rust when drilling holes in steel, or the hassle of using a hammer drill in concrete.
Lastly many concrete garages are guaranteed for 10-15 years, although a well treated timber garage will last just as long and has the advantage that any of the wood can easily be replaced in the event of rot or damage. Indeed one that is made of 100% pressure treated timber can last a lifetime.