without putting up earnest money. And you don't move in until the seller is pid in full.

Go to the doctor - you pay a copay and provide insurance info. No insurance? Then the up front payment is usually higher. You're going to buy gas? Your credit card gets a pre charge of $75 which gets knocked down to the true amount when you're done.

And other situations have collection mechanisms that aren't available for legal services. Have work done on your house and you don't pay? You get to deal with a mechanics' lien.