The Westchester residential housing market, including single family, condo, co-op and multifamily sales, reflected price stability despite the highest sales total in at least 34 years and falling supply. Median sales price for all residential properties edged 0.8% higher to $529,000 from the prior year quarter, while the remaining price indicators showed mixed results. Average sales price slipped 2.9% to $696,654 and average price per square foot increased 4.9% to $319 respectively from the prior year quarter. Countywide the number of sales expanded 5.5% to a record of 3,044 as the amount of inventory slipped 2.7% to 5,653 respectively from the same period last year…