Real Estate Laws Ontario

Looking to see what grounds I have against a previous owner/seller of the home I currently live in.

Me and my Mom bought this house (century old home) that was supposedly in our price range except it had knob and tube wiring and our lender (we had to go with a B lender due to me having a completed certificate of full performance from a Consumer Proposal). We had set an offer for 650,000 for the house as it was listed for 679,000 or something rather and it being on the market for some time. They owners rejected the offer and said that we can purchase at 670,000 after they hire an electrician to remove the knob and tube. We agree to that..

I’m not sure if in our conditions we didn’t have the house inspected because there had been an inspection done before the house went up for sale. I personally haven’t seen the house inspection report but my mother claims she’s read through it.

Fast forward to about a month into owning the house.

We find out the upstairs toilet is leaky and that the laundry closet that was on the floor below was not vented properly so mold grew in the ceiling and along the OSB board. They had put up. Mom and I tore out the mold ourselves.

We were told by the real estate agent that the furnace was replaced earlier in the year ( I believe that and saw the install date on the furnace) but I don’t think I’d set up properly or the ductwork is sufficient for the system. I will explain my reasoning below

This house is 2 floors with an unfinished basement and an addition put on in early 2000s. The upstairs only has one huge black heat register and it’s in my room, and none of the white registers in any of the other rooms produce any hot air. This is the same for the main level, I have only found that one or two vents actually produce any hot air and that everything else seems to be doing nothing. We are only finding this out because the temperatures gotten a lot colder now and the furnace seems to be turning on every 15 minutes for 5-10 minutes non stop at night.

We have an oven that doesn’t get vented out properly and now we are finding that there’s a clog in our sewer drain.

TL;DR : bought an old house with a lot of not in plain sight problems and I am finding them out week by week as I live in the house. Looking for legal ways of approaching previous owners for lack of disclosure.