I'm thinking about getting into home-brew but due to space constraints likely only have room for a 1 gallon setup (and that's all the beer I need anyway).
Before I go that route, though, I wonder if getting a smaller set-up will have any impact on the quality of beer I'll be able to produce, and what my options may be for a robust process where space is limited.
Work hygienic, and try not to splash with your mash or wort. That is the main point in getting a quality brew.
I started also in the kitchen brewing batches of 4 to 5 liter. The advantage is that you can do a whole lot with things from your kitchen. In the meantime I moved up a little bit, but I still brew mostly 5 to 8 liter.
The advantage of brewing small is that it is easier to do more brews, and you have shorter brew days. I prepare my water and my crushed malt the day before, and then start the next evening around 5 PM, and I am finished between 9 PM and 10 PM.
Brewing small makes it also easier to move things around.
The biggest issue you will probably notice (assuming you're in the US) is that most of the extract kits you can find in stores are 5 gallon kits. Ordering 1 gallon kits will be more pricey ($14 for 1 gallon extract kit vs $31 for 5 gallons).
The biggest challenges in your environment will be light and temperature. Light is bad for beer and bad for fermentation. The smaller batch size means the fermenting wort will be affected more by temperature fluctuations. One way to help address both of these issues is with a Neoprene sleeve. It will help insulate the wort from temperature changes and light during fermentation. The problem that can arise with this solution is visualization of the fermentation process. I rely (probably too much) on what is going on with my soon-to-be-beer visually. I know about how active my main-stay brews should be, the colors and smells, and the trub at the bottom.
Depending on your space, don't be afraid to brew up! I have two 5 gallon carboys sitting nestled on home-built shelving in the least visited area of my basement with the wall-studs supporting the back and a strap to keep them from accidentally getting knocked off. Getting the 5 Gallons to the upper shelf is physically demanding. Luckily, I can handle it.
Don't be afraid to look around and see what other homebrewers are doing. Zymurgy Magazine even has a "pimp my system" section where you see new and innovative things people are doing. If you like/understand coding... some of the Raspberry Pi setups are incredible.
You can make the same quality beer in a 1 gallon system as you can in a large even commercial system.
Really the only con is the volume size, when you make beer you usually want more than the 10-12 beers a 1 gallon system will yield.
Everything is much easier at 1 gallon. Simple things like maintaining a mash temperature become more and more difficult the larger the system gets.
You can do 1g batches usually with just a few low cost purchases. Medium stove top pot, BIAB bag, 1g glass wine jug, airlock, hydrometer, few flip top bottles is really all you need to do all grain brewing at that size.
Once you want to upsize your volume, maybe look into the Grainfather brew system. Very compact, easy to use and can yield 5g.
