Before you purchase your first Finches, you must understand the commitment you are about to make. Finches aren't necessarily difficult to keep, but they do have needs. One day without appropriate food or water could be life threatening. Some species are easier than others. For instance, a beginner may want to start with a pair of Zebra or Society Finches, as they are some of the easiest Finches to keep. Finches are NOT solitary animals and need pals to hang out with. Two finches of any species is the minimum. Do some research before you get your birds to make sure Finches are right for you. They don't talk to you, but they will certainly sing to you. Some sing more than others. Typically only the male Finch sings. Once you've decided that finches are the right pet for you, decide how much room you have available to give to the finches. Are they going to be kept inside or out?
Inside: A small cage (30"x18"x18") is ok for 1 pair of Zebra finches, but bigger is always better! Don't locate the cage too near the kitchen or any other place in the home where there may be fumes. Finches need a full days worth of sunlight, so placement near a window would be great as long as the birds can get some shade. You will need a supplemental light source if not enough natural light is available or if your windows have a UV blocking coating. Normal household temperature is fine. If it's comfortable to you, it is fine for your finches although Gouldians prefer temps around the 80 degree range.
Outside: A large aviary or walk-in flight would be supreme, but a smaller cage will do, if it's not too crowded. The aviary has to be protected from the elements either by having a sufficient roof or by being located under a covered patio. There is always a flight risk if you don't have some kind of safety catch or screened in porch where your birds are located. You will also have to consider that no matter where you live, there will be predators that will want to eat your birds or their food. You will need to take precautions to keep your birds safe. The temperature where I live in south Texas is" HOT" in the summer and "NOT AS HOT" in the winter. :) Finches are birds and birds naturally live outside. When your birds are acclimated to the outdoors, they should do fine all year round. During cold weather I have a heat lamp in their cage in case they need it. My Gouldians typically stay outdoors even in the winter but I would recommend monitoring your birds closely and evaluate how they are coping with the cold. Certainly consider bringing them indoors if the temperatures stay under 40 degrees for a prolonged period. On the extreme hot days, over 98 degrees F, I run an oscillating fan to move the air around a bit if they seem distressed or panting. No matter the temperature outside, sufficient protection from elements is of utmost importance. A clean, dry environment will keep your birds happy and healthy.
Food: There are many different varieties of finch food on the market. I use Volkmans Super Finch but you can use different kinds of finch seed and mix them together. Volkman finch food is a great seed, but can only be bought online from what I've seen or at bird fairs. Whatever seed you choose, stick with it or gradually change from one to another if you must. Gouldians are quite sensitive to sudden changes in diet. So before you purchase your new birds, be sure to have some of their preferred food so as not to make radical changes too fast. Millet is a staple in my aviary. Finches love it and I always make it available to my birds. I also give them fresh collard greens, carrot, corn, broccoli, or strawberry on occasion. They have access to a cuddle bone, grit, (dried) egg food, herb salad, and dried greens all the time. Supplements like Calcium(Calciboost) may be needed if your birds are kept indoors along with a full spectrum light. Just make sure you give your birds the necessary nutrients to keep them healthy and happy.
Medications: SCAT - I use a few times a year to treat all my birds. It prevents/treats air sac mites. SEVEN DUST (mite dust) can be used in the bottom tray of your aviary, under the corn cob, to keep mites and other insects away but the birds should not come in contact with the dust. DIATOMACEOUS EARTH (insect control and de-wormer) can be used safely in aviary and on birds to control insects naturally. It is a good idea to have a SURVIVE or GUARDIAN ANGEL around incase of sickness. A broad spectrum antibiotic wouldn't hurt either. A clamp lamp with bulb is another basic necessity when dealing will under the weather birds. It's a good idea to have a small separate cage available in case you get a new bird or have a sick bird. This way you can keep the bird separate and treat it as necessary and keep the rest of your flock safe.