My grandfather owned a dozen apartment buildings, and when I asked him when I was little how he got so many, he said he just bought one, and then used it for collateral to get the second, and so on.
He has since passed away, but he wasn't the sort to give in-depth explanations anyway, so either way I would've ended up turning to another source.
What I'm trying to figure out is basically how that works. Do you have to own a building completely before you can use it for collateral to secure a loan? Or is there a threshold of ownership you must cross or something like that, like a percentage? Or is it that you only use as much as you own, as in a loan equivalent in value to the percentage of the building you own?
Example for clarification:
I buy a $100,000 house by putting down a $20,000 down payment. Now I want to use it as collateral to buy another, identical house. Can I get a $100,000 loan, or only $20,000, or do I not own enough of the house to do that yet in the first place?