I'd say how much you put down depends on your plan.

We do not charge this fee nor do we feel that it should be charged unless there is a specific reason behind it.

I wish I could be better help on specifics, but this is just the start of the process.

There is money in buying raw land and getting it permitted for build with plans and flipping it shovel ready 

The minimum rate of return you should aim for in a house flipping venture depends on various factors, including the local market conditions, your level of experience, and the specific risks associated with the property.

the best plan might be to charge you full price then refund the money equally to you and your sister to avoid maximum taxes. 

I found the owners information and am planning on reaching out.

The plan regarding primary residence is to finish the basement out to increase a number of bedrooms and capacity for the short term rental.

I don't necessarily have specific questions because I am just learning everything. 

My wife and I plan on buying another property at the end of this year and will probably move that property into the LLC or Trust as well.