The combined deals, once completed, will add to the $8.6 billion that occurred in the September quarter, making this year one of the busiest.

In the pipeline are also the properties at 420 George Street, 175 Castlereagh Street in the City as well as the number of industrial and office assets ear-marked for divestment in the suburbs.

Brookfield this week announced it was selling its half share of the World Square shopping centre and car park, while Charter Hall has a combined $700 million office and industrial portfolio up for sale.

According to CBRE, offshore investors continued to dominate commercial property sales activity in Australia in the third quarter.

In Brisbane, DEXUS Wholesale Property Fund (DWPF) settled the $635 million acquisition of Waterfront Place and Eagle Street Pier in Brisbane.

Property investors are also awaiting on any news of the sale of David Jones' department stores. The new owner, the South African Woolworths, has said it is reviewing the property portfolio and could sell one of the Melbourne sites and the Sydney Market Street store.

David Jones' Market Street would be attractive to a developer looking to build apartments with retail on the ground floor.

CBRE's sales analysis takes into account sales of retail, industrial and office property valued at over $5 million.

It shows that offshore buyers accounted for 56 per cent of total sales, by value, during the quarter – the highest proportion recorded in the ten years of record keeping by CBRE.

CBRE's head of research, Australia, Stephen McNabb said the high level of overseas purchasing activity had pushed total sales in the quarter 8.5 per cent higher than the corresponding quarter last year.

"Given the current level of transaction activity we are on pace to reach the record $29.6 billion in annual sales recorded during 2014," Mr McNabb said.

"The major source of new capital has been China, with Australia attracting close to 25 per cent of the US$6.5 billion in Chinese investment capital released into global real estate markets in the first half of this year.

Major Australian acquisitions in third quarter were boosted by the $2.5 billion purchase of the Investa portfolio by China Investment Corporation.

Singapore's Ascendas​ Real Estate Investment Trust was another significant investor during the period, having snapped up a portfolio of 26 logistics properties from GIC in a deal valued at $1.01 billion.

The deals come as Moody's Investors Service says that its outlook for the Australian real estate investment trust (A-REIT) industry is stable over the next 12-18 months. The stable outlook reflects Moody's expectation that the sector's operating income will increase modestly.

In the coming weeks, the A-REIT sector will also pay out its final dividends, which can cause some volatility.

Maurice O'Connell, Moody's vice president and senior credit officer, who authored the report on the outlook for the A-REITs said the industry's aggregate annual comparable net operating incomes should grow at around 2 per cent during the coming 12-18 months, as rents on existing leases rise.

"This growth rate is broadly in line with that of the last 12 months, ended 30 September," Mr O'Connell said.

"The retail segment will see slightly higher income growth rates than the office and industrial sectors."

On the office property segment, Moody's report says that improved supply-demand fundamentals in Sydney and Melbourne outweigh weakness in the resource-centred cities of Brisbane and Perth, benefiting GPT Group and DEXUS Property and weighing on Growthpoint Properties Australia Ltd.

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