The sales slump sweeping across Toronto's housing market extended into September as buyers and sellers continued jockeying for position in the wake of the provincial government's 16-point plan to improve affordability.

Sales across the Greater Toronto Area sank 35.1 per cent year-over-year last month as 6,379 properties traded hands, according to data released by the Toronto Real Estate Board on Wednesday.

The average selling price in September was $775,546. While that marked a slight uptick from the year-ago period and August's average price of $732,292, it was still almost 16 per cent below the April peak of $920,791.

Prospective buyers had more selection to choose from last  month, as active listings surged 69 per cent year-over-year.

“The improvement in listings in September compared to a year earlier suggests that home owners are anticipating an uptick in sales activity as we move through the fall," said TREB President Tim Syrianos in a press release.

"Consumer polling undertaken for TREB in the spring suggested that buying intentions over the next year remain strong," he added. "As we move through the fourth quarter we could see some buyers moving off the sidelines, taking advantage of a better-supplied marketplace."

The region's housing market has been in flux since Ontario Premier Kathleen Wynne's Liberal government introduced its so-called Fair Housing Plan in late April, including a 15-per-cent tax on foreign speculators.

There was extreme divergence across property types in September. At the upper end of the market, detached home sales sank 40.4 per cent year-over-year, while the average price was unchanged. Meanwhile, condo sales fell a more modest 27.5 per cent but the average price jumped 23.2 per cent.