A good mirrorless camera and a prime lens should last you a decade, capturing sharp photos and handling low light way better than your phone ever could. Buy the right kit once instead of settling for an entry-level body you will outgrow in six months.
Watch the release cycles closely because camera brands drop new models every fall, making last year's proven bodies drop significantly in price. Holiday bundles often toss in extra gear or discounts that make that older body an even smarter buy.
That 0% window is a hard deadline, not free money, and any remaining balance left when it ends will trigger steep interest charges on the whole original amount.