The City of Vancouver is looking to buy some expensive real estate, but it remains unclear what the cost might be for taxpayers.

Tomorrow councillors will vote on Mayor Gregor Robertson's motion asking staff to look into buying or leasing Granville Island from the federal government.

And in a letter to residents this past weekend, Robertson revealed the city has offered to buy the Arbutus railway corridor from Canadian Pacific Railway.

No price was named for the railway land, which is some of the most valuable undeveloped property in the city, but Robertson says an independent appraisal has been made, and they are prepared to pay fair market value.

So far CPR has not been receptive to multiple offers according to the mayor.

The railway and the city have been fighting over the future of the corridor for more than a decade, with CPR seeking to develop it into a mix of commercial, housing and green space, and the city seeking to preserve it as a green space for community gardens and a route for bikers and walkers.

In 2006 the Supreme Court of Canada ruled the city has the right to control any development along the 11-km strip of land connecting False Creek with the Fraser River. The city has rezoned it to prevent any development.

But CPR, which has owned the land for nearly 130 years, still has the right to run trains down the urban corridor, and  recently warned it intends to do just that, giving residents until the end of the month to get rid of dozens of community gardens and sheds on its land.

At Tuesday's city council meeting, Robertson will also  ask city staff to look at options for buying Granville Island from the Canada Mortgage and Housing Corporation, following recent revelations that the federal government is considering handing control of the island over to the Port Metro Vancouver authority.

Robertson has publicly opposed that idea, saying the popular tourist destination should be controlled by local governments.