This is a room underneath a front porch it's in a colder climate (TORONTO). It has a poured concrete landing. There was mold coming through the drywall so I took all of the drywall off to reveal the worst basement build I ever have seen. I estimate it was built about 25 + years ago. It's a solid cinder block base but halfway up the wall they used a darker cinder block material that was not as strong and is turning to dust. They used clay pavers instead of bricks to fill the corners that are also turning to dust and most of the upper mortar is 50% effervescence now. The bottom half of the cinder block is still strong and durable.
The leaky concrete landing on top has been repaired a few times in the past but still contains hairline cracks throughout, it's roughly 5 inches thick slab approximately 8 x 8 feet with no relief cuts, it's a lot of cement to remove and take away. Plus it has a stone finish that was never sealed so I filled in missing grout and sealed it for now in hopes that it will help it to stay dry until I decide what to do. I want to avoid a total demolish and digging, I think I can replace the upper cinder blocks one at a time. I'm perplexed and need any guidance you can give me. Thank you in advance.