HI Uday,I see a stucco crack by the door on the exterior (possible foundation issue) and possible rotted wood in one of the exposed walls, plus the shingles on the eaves looks wavy (rotted wood) and possible large ceiling leaks (more possible rotting of the roof), plus a lot more.Also electrical code might require you to update to modern code.It looks like a lot of unpredictable labor (possible cost over runs) and possible extended unpredictable hold time.You could get bids for everything that's wrong with it, if you understand what's wrong with it.The first step would be to get a home inspection and take it from there.Roof, foundation, electrical, etc....

Now the AC unit was 1 year old at that point, and I had just had the roof redone in architectural shingles that spring.

Three units have no coverage for roofs as they had T lock shingles when I bought them and have not replaced them. 

I can remember crawling around on the roof of our house pulling loose shingles off when I was 12. 

My roof is 4 years old asphalt shingles and my insurer is Lloyd's of London.

I sold a beachfront home last year that was ICF constructed in 2000 with a metal roof on concrete pilings and the insurance went up triple what my larger 2019 stick built with shingle roof 6 lots down is. 

I don't expect to have any outside work for AT LEAST the next two months, so next week I'll be up on a roof doing the "delightful" job of removing shingles on one of my rentals, followed by a bunch of painting & gardening.