Rising prices, cooling sales, and more inventory characterized the Riverdale market. Median sales price rose 8.3% to $305,000, the fourth consecutive year over year increase. The number of sales declined year over year for the third time over the past four quarters. There were 85 sales in the first quarter of 2019, down 37.5% from the year-ago quarter. Conversely, listing inventory expanded year over year for the third straight…