It is up to you if you want to go thru the steps of brumation. For pet snakes it is not necessary. Personally I did not bother with it the first couple of years. The last two I have, using a wine cooler (the commercial kind for keeping bottles of wine in the 50-60 degree range), which I got second hand off craigslist, for just shy of $1000-, but you can get a new one for around $2200.- and up. For just a few snakes it probably is not worth the trouble and expense. This winter I'll be keeping an entire room air-conditioned (I am in Florida) for a few months. This will save me (the expense of) about 300+ meals per week. The babies and juvies will be in another room & kept warm so to continue their growth over winter.
Keep in mind if you do not have the ability to regulate the temperature and the temps go up and down a lot (radically), this can lead to respiratory disorders and other conditions which can lead to costly consequences. It is really up to you.