House sales dipped in August in Greater Des Moines, while median sales prices increased 3.5 percent, the Des Moines Area Association of Realtors said. Sales dropped to 1,392 from 1,462 in July and 1,415 in August 2017. The median sales price last month was $208,000, compared with $200,800 in July and $192,800 a year ago. Pending sales dropped to 1,364 in August, compared with 1,484 in July and 1,266 in August 2017. Houses that sold in August had been on the market an average of 45 days, one day longer than houses that sold in July. The average number of days on the market for houses that sold in August 2017 was 57. Inventory increased 6.2 percent from July to 3,893 active listings.