Meanwhile, a full size bulldozer arrived on site.

I was looking for one person due to size of unit which is how we rented in the past but have had alot of couples interested which l turned away.

Depending on price and size of the building will also determine amount but I would guess start with $5-10k at the beginning and as it cash flows add money to the account till you reach 10% of the value of the building.3.

Size? 

If you think you have the ability to raise sufficient equity to do the deal your best bet would be to find a local developer with expertise in this type of project to partner up.

You're right to say that there is no one-size-fits-all number, so buckle up for hearing anything and everything.  

different banks have different risk thresholds. if the state has a real property disclosure form requirement, then seller would be required to disclose in the future. sometimes tanks can be closed in place especially if the state does not regulate the heating oil tank (depends on size) and its close to house(basically fill with sand). but you can do sampling to show that the tank has not impacted the property.

Cash for keys is going to be your best bet.

Stores will sometimes put store specific leftover boxes on sale and it might just be enough for your project size.

I use a good sized local bank who lends their own money and keeps the mortgages in house.