Yea good luck, more than likely you have Heritage listing and Demolition Control applied. Had one myself in same area and just sold it as the cost to renovate at "cost" was going to be huge and yes would have been a great house at the end but would have had to live for over decade to even try recoup money spent.

You will have a huge list of things that you must do during the reno to ensure you don't break any heritage listings etc.. Like can't just tear back to the frame and rebuild, you must have the front redone first as is once you get approved then you can move on to do the back of the house etc..

Can always try the "drop the house" when its getting lifted to build under.