Home sales in the Detroit metro area rose in September for the third consecutive month as sale prices also jumped, a new report says. However, for the hardest hit areas of the city, opposite trends persist.

In the city’s inner-ring suburbs, sales fell 6.8% compared to September 2010, but that decline was offset by gains in outer-ring suburbs, which pushed year-over-year sales in the greater Detroit metro area up 8.2% overall, according to a report from Realcomp.

“Prices are higher [in those areas] because inventory has dropped so dramatically from where we were a couple of years ago,” said Karen Kage, CEO of Realcomp, the largest realtor-owned multiple listing service in Michigan.

The inventory of all MLS properties fell 18.1% in September from a year earlier, the report showed.

Meanwhile, prices surged 10.1% in the larger metro area, to $74,900 from $68,000 in September 2010. Sanilac, Tuscola, and Lapeer counties saw the biggest gains, with prices rising 44%, 31% and 29%, respectively.

The largest decline in the metro area was registered in Huron County, where prices fell 35% to $68,000 from $104,500 a year earlier.

Foreclosure sales in the greater metro area fell 11% but were offset by a 23% increase in non-foreclosure sales.

Foreclosure sales in Detroit dropped 15.8%, while non-foreclosure sales rose 12.5%.

Despite the drop in distressed sales, prices in the central Detroit area are being driven down by the ongoing glut of foreclosures.

Central Detroit median prices have plunged from about $49,000 in 2006 to just below $37,000 in January of 2007 and then $21,500 in September of that year. However, now prices are starting to bounce back after hitting a low of $5,737 in February 2009.

This year, about 13.5% of the 5,720 sales closed in September were identified as short sales, and 45.3% of properties sold were paid for in cash, according to Realcomp.

Write to Liz Enochs.