The 4th unit will take longer as we need to demo the living room, bathroom and bedrooms completely and rebuild it all.

See if you can tag along on a few projects to learn (tell them you'll help demo, paint, etc. for the learning experience).  

Looks tough to be able to get that in anywhere without doing some demo.

If I plan to purchase the property as is, demo all the structures on the land, and rebuild, will a big bank help, in terms of lending, on the purchase + demo + rebuild costs? 

Also doing the demo work could dramatically reduce your costs, no one likes doing demo.

Is there any value in demoing the house and replatting it into 2 or 3 lots?

I knew this was going to be a big ticket item and set aside a large budget number for it.To make things worse, I began watching videos on YouTube that compiles the entire process of demoing and re-plastering a pool.

Most of the interior demo has been done.  

@Nhia Yang, have you spoken with a commercial lender?

Demo estimate is $8-10k, back taxes due are $4k.