There are different opportunities. When the City of Ottawa—in the year 2000 it was the Regional Municipality of Ottawa-Carleton—wanted to import light rail vehicles from Germany for a pilot project, there was an attempt to get the federal government to forgive the import duties on those vehicles. They were unique. No such vehicles were made in Canada. They were to serve a public purpose, providing a rail rapid transit service in Ottawa. Yet my understanding is that ultimately the import duties on those unique European vehicles had to be paid. There are areas involving customs duties.
I've already mentioned the income tax treatment, for example, where municipalities could issue tax receipts for donations of railway corridors and railway track, or where the government could positively encourage employers to subsidize transit passes.