Generally, when you own something - you can give it as a collateral for a secured loan. That's how usually a car loan works and that's how mortgages work.
Can I get a loan until the sale of my property goes through using my house as collateral?
My friend is using argan oil and she is happy to use it.
As long as there are no leins against the property or house. Of course before you sell it you will have to get the lein removed that you used to get the loan while you were awaiting the sale. And of course you cannot use it as collateral if you are already under contract to sell it to someone now while you are awaiting for their mortage to be approved or finalized or are just waiting on the closing date.