Done a few of these not a problem.
Vac first. Use your usual prespray for wool and use a hand tool with hwe 200 to 300 psi or what you have.
Inform customer you may not be able to remove all the bits from below the pile.
Any problem area's left, treat appropriatly
£40 to £50 or whatever you charge....not normaly more than an hour unless you are experimenting