According to 2018 Zillow® Group Report on Consumer Housing Trends:
The median income for a first-time buyer is $72,500, compared with the national median household income of $60,700. The difference in income for first-time buyers is more pronounced when compared with their peers who didn't buy, who have a median income of $42,500.
On average, first-time home buyers have a median down payment of 14.5% of a home's price; not the typical 20% down payment used by 58% of repeat buyers. The Zillow article goes on to note, however, that while repeat buyers are able to use proceeds from a previous home sale as the downpayment for their purchase, first-time buyers don't have this option. In short, first-time home buyers with higher incomes have the advantage of being able to save up for their down payments quicker.
The not-so-good news for Southeast Florida is that the median income of our first-time home buyers is below the nation average. This, combined with housing prices in our region, means that our first-time home buyers can afford less than 40% of our current housing stock.