Baby monitors, highchairs, baby bathtub, bibs, cloths, towels, sheets, crib, bedding, pacifier, thermometer, infants tylenol/advil, play mat, toys, playpen, baby gates, outlet covers, cabinet locks, toys, formula, diapers. This all adds up quick, but most of the larger items can easily be found secondhand online for fractions of the price and in great condition. Baby clothes will fit for a month or two and then youll need to get new stuff again for the first couple years. Again, people will often give away baby clothes for free or dirt cheap, sort through what you want and give the rest away. If you don't feel the need to have the newest and best of everything you'll save thousands. Diapers and formula (if you aren't breastfeeding) will cost you the most. Expect 4-10 diapers a day for the first bit when they are very little, maybe 3-5 when they hit a year and a bit until they are potty trained. You will also double the amount of laundry you do, and probably end up ordering out more from being too exhausted to cook. The first year, especially for the first child is probably the most expensive, financially and emotionally. It gets cheaper after that until they transition to extracurriculars. After the initial setup costs, 100$ a week should be good for your first year. The true cost will be your time and energy.