Purchase volume was mostly up while median prices moved in different directions for two neighbor island housing markets last month.

Generally, sale prices were up a little on Hawaii island and down by a bigger margin on Kauai, according to a recent report from Hawaii Information Service based on data from the Hawaii Island Realtors and Kauai Board of Realtors trade associations.

The median price for single-family homes on Hawaii island rose 5 percent to $320,250 in July from $305,000 in the same month last year. The median condominium price rose 4 percent to $295,000 from $285,000 in the same period.

The number of sales on Hawaii island edged up 3 percent to 219 in July from 212 a year earlier for single-family houses. And there was a spike for condo sales, which rose 60 percent to 77 units last month from 48 a year earlier.

On Kauai the median sale price for single-family homes tumbled 25 percent to $565,000 last month from $750,000 a year earlier. And the median price for condos slipped 8 percent to $360,000 from $391,000 in the same period.

Large swings in the median price for neighbor island home sales is not unusual because relatively few sales are involved, and that means differences in the age, size, quality and location of homes sold can have a bigger impact on the median, which is a point at which half the sales are for a higher price and half for a lower price.

There were 51 single-­family home sales on Kauai last month, up 28 percent from 40 a year earlier. The number of Kauai condo sales was unchanged at 32 in the same period.