If you search a bit on the internet, you'll see a lot of different home wine making setups. Some will make you sigh with envy--an entire converted garage or outbuilding, or part (or all!) of a basement, and even dedicated cellar spaces that look like a generation of professional winemakers have thought them out.
You don't need a giant space, or even a fully dedicated room to make your wine with Master Vintner--just a few simple conditions and you'll be ready to make your best wine ever, in any space you can spare. Here are a few guidelines though, to help you decide on the best spot.
1: Floors that can be mopped
You might live in a small enough place that even if you can set your fermenters and carboys (try a Big Mouth Bubbler) in a little closet, you probably can't do your mixing there. Remember, you're playing with sticky, stainy liquids. It's a pretty good bet you won't want to be splashing around in your buckets in the middle of your living room. Unless you feel your carpet would be improved by soaking in wine!
Make everything up in your kitchen, or if there's enough space, in your bathroom, before moving your wine to the fermentation area. Working in a room that's designed for water ingress and spills will save a lot of heartache (trust me). Just be sure you have a way of moving the heavy fermenters so you won't injure yourself.
If you do have a space to dedicate solely to wine making, with impermeable floors and access to a sink for cleaning, so much the better!
Your Master Vintner kit wants to be kept in the range of about 65°-76°F (18°-24°C). It's one thing to be in this range, but even more importantly is that the temperature has to be consistent and steady: big fluctuations between very warm in the daytime and quite cool at night will drive your yeast crazy. It could make off flavors or even stop fermenting! This is why basements are great, because the space below grade is very slow to heat up or cool down. It's even steadier when you can arrange your wine making space up against the north wall.
How can you tell if it's steady? Go to a garden shop or home improvement store and get a Min/Max thermometer. They've got a dial with two stops on it and it will measure the lowest temperature and the highest temperature over any period of time you choose. Fancy electronic Min/Max units are available, but you can get by with the cheapest one you can find.
Fluctuations of more than two degrees up/down over the course of a day are acceptable, but five degrees is pushing it and you might need to look at insulating the area or putting in a space heater. Over longer timelines, a fluctuation of ten degrees between winter and summer won't be critical--completely steady temperatures might be achievable if you live inside a cave, but probably not in a house you'd want to live in!
If you live in a very hot climate (Florida, Arizona) you probably already have air conditioning. As long as it extends to your wine making area, you're golden. If not, a swamp cooler or portable air conditioner might help you keep the temperature steady, and a thermostatically controlled space heater can steady out a colder climate.
Your wine making space has to be very clean. You wouldn't prep your dinner on a dusty counter or serve a meal on a sticky table. Wine making is literally food preparation. Your space needs to be easy to clean and free of dust and insects, and also free of random intrusions from other household members – including pets.
You should have enough light to work in, but no exposure to direct sunlight or excessively bright lighting. While UV exposure isn't as bad for wine as it is for beer (which can be ruined in only a few minutes!), bright light doesn't do the wine any favors. As long as you're using standard lighting fixtures (anything you'd put in your kitchen or living room) you won't hurt your wine and you'll be able to see what you're doing.
Using great raw materials is the first step to making great wine, and following the instructions is the next, but the conditions around you are just as important when you're making up a kit. It might take some creativity to make your wine making space work, but thinking of the delicious end product should inspire you!