I plan to brew some type of ale as my first beer, i heard it is the easiest to start with. I was wondering what is the good small amount of beer to brew first time (or minimal amount possible) as i would like to keep it low in case i do something wrong and i currently also do not have a lot of space to keep it all (no garage for 50L of beer to sit for a couple of weeks).
This is a matter of personal preference, of course, but I suggest using a standard 5-gallon recipe (19L) but then cut all the ingredients in half and brew just 2.5 gallons (9.5L). Then if you like it, you can brew it again, and if you don't like it, then you've only lost 2.5 gallons (9.5L). You will get about 1 case of beer, at least 24 bottles or maybe up to 27-28 maximum, per 2.5 gallons (9.5L).
Personally, I often brew just 1.25 to 1.67 gallons (5-6L) at a time when experimenting. You could also do that. Simply use fewer ingredients. The fermentation still takes the same time regardless of recipe size. With smaller batches, there is no need to boil the wort vigorously or else you will concentrate it too much. Just bring the wort to a slow simmer to reduce the boiloff rate.
Hope this helps. Cheers, welcome to the hobby, and good luck!
There are certainly 1 gallon kits (3.7L) kits available and you can start cheaper and brew more often doing so. I suggest going this route to begin with until you decide if you really like the hobby. Good brewing software can help you scale recipes meant for larger batches to whatever size you like. I generally convert grain bills to percentages when scaling them for my equipment. Hops are a bit more involved and something like brewersfriend.com recipe builder will help you adjust to match the original recipes IBUs. They actually have a number of brewing related calculators that'll help get you started.