Your first condo is less about a building and more about what happens inside it. The short walk to the train. The kitchen that finally fits a real table. The lock on the door that is actually yours. A starter condo suits someone who wants city access, lower maintenance than a house, and the freedom to paint a wall purple without asking a landlord. The catch is that "affordable" still means six figures, and most of that number is not flexible.
So the goal here is simple: put down as much as you can honestly afford, keep the monthly payment inside your real budget, and use a 0% intro APR window only as a bridge for the gap you cannot cover from savings. Numbers below are for a roughly $265,000 condo, which is close to the median for a starter unit in much of the U.S. Your market may be higher or lower, so treat the figures as a starting point, not a quote.
The 15-month intro APR is a deadline, not free money. If any balance is still on the card when month 15 ends, the regular APR on the Discover it® Cash Back applies to what is left, and interest starts compounding right away. Pay it off inside the window and the plan works. Drift past the window and the same purchase that felt clever starts costing you real money every month.