Can someone help me understand how to start up

[Michael Bell]

Ok when I viewed the path to purchase series I saw that on the expenses portion it uses a tool to calculate how much time it would take me to get 20% of I started with nothing, however it only came to $1800 in 18 months. I know that the houses out here are a pretty penny and I'm sure 20% would be far greater then $1800 so my question is, what am I basing this on? If my credit is great? If the house is only $100,000 or less? Is this tool not exact or should I really feel like it will only take as little as $1800 to get started? I have never owned a property and I am really interested in getting started and I have absolutely zero money saved right now and I want to change my financial status as soon as possible. Can anyone help me.