We have this in CA where all sales including private person to person and gunshow sales must go thru a dealer witha ten day wait.
At an out-of-pocket cost per gun of about $50 charged to the purchaser, for background check and paperwork. This doesn't count the purchaser's time, trouble, or transportation expenses.
All of this money is completely WASTED since there is no evidence than any such gun laws have a beneficial effect on crime rates.
Every day I hope for the coming collapse of Kalifornia's government. Only when school teachers and other public employees realize that there is no money for their pay, will they consider the effects of suspending the costly infringements of my right to keep and bear arms. When that time comes, I will let them eat cake.