Why don't you just build a base out of 2 x 4's to raise the whole cabinet assy up 3 1/2"? Disconnect plumbing, sink top looks to be cultured marble, one piece. Should just be held down with caulk. Pop it up and remove, find the screws holding cabinets to wall and remove. You will have to more than likely trim supply lines off below shut offs to remove cabinets. Install the base, cover the front of the 2 x with white toekick material (thin plywood painted white) and reinstall plumbing. Mostly your labor, not that much in materials.