I personally buy buildings that either have limited commercial exposure in relation to the total units or building SF or alternatively buildings that possess commercial spaces that are large enough where placemaking can attract amenity tenants that benefits my residential real estate in close proximity.

.- Titled land/property in desirable areas is not cheap, and you better know what you're doing if you're buying Right of Possession land

It’s 2 years before you take possession on a house.  

How do I know when I may take possession of the property?

The winning bidder gets the right to possession, but usually cannot exercise DIY possession.

contact senior lender or trustee if you can, tell them your a junior in possession and ask them to post pone the sale for 90 to 120 days so you can do a refinance on it.. 

There are NO possession rights with only a tax lien certificate.

If this were not a section 8 tenant, you would need to prorate the rent based on the lease start date documented in the lease agreement regardless of possession (unless the lease states otherwise).4.

I'm also assuming if you are taking possession mid-August that you wrote in the contract to get prorated rent for that month?

I've learned that a little bit of naivety is good because otherwise an individual may never take the leap if they possessed all the knowledge and truly knew how much risks are involved.