Yes.
And unless they finish it in one fail swoop (as they should), don't pay it all up front.
Half now, half when it's finished to your satisfaction, and guaranteed for X many years stated in the contract from the finish date.
And unless they finish it in one fail swoop (as they should), don't pay it all up front.
Half now, half when it's finished to your satisfaction, and guaranteed for X many years stated in the contract from the finish date.