We kept everything that DS1 used and so didn't need to buy anything really! I 'shop around' to buy consumable stuff like wipes when they are on special. We did need another carseat for DS1 but would have had to buy that regardless of whether we had another baby or not as he is now 3 and a half. I have two boys so we've reused most of the toys and clothes and have only had to get a few new items for DS2 so far. I know once he's older and doing swimming etc too we'll have those expenses to consider but like others have said, you live to your means. The biggest unexpected thing for us is that DS2 has had a few health issues that have required regular medication, specialist visits etc. Nothing major but still things that cost us money with him that we never had to pay for with DS1. So it might be worth considering that if your next bub had any special needs like that, would you be able to afford to meet them?