Typically, at least one months salary.

Get a NAR contract from state your in and use that for the agreement - best place to get one is find an investor friendly agent on BP and they typically will provide one for free or a small fee

how long does it typically take?

@Bob Bowling if the lot rent is 200 and the home rent is 300 to get to 500 monthly total rent, minus typical expenses (33% of $300 for this example) this gives a 1982 mobile home a net of about $200 per month or $2,400 per year at a 10% CAP gives each home a value of 24K using an income based approach, which is overpaying - this home can only be sold for about 5K in the real world.  

Then I got to thinking about some questions:What are the typical exit strategies with partners on a BRRRR deal or a rental deal?

How is the typical PMI percentage ?

If you start in commercial typically it will be smaller deals say 1 million or 2 million.

Typically there is between that point and closing (when you actually own the property) there are several weeks or months for due diligence and for financing to get lined up.  

Hard money lenders will typically set their own rates with little to no room for negotiation unless you have developed a relationship with them.

Typically, there is somewhat of an inverse relationship between Net cash flow vs. price.   2% rule is usually easier to get at lower priced homes under 100K.