Hello Abinash, Correct me if I am wrong in my guess that you liked the basin so much that this entire unit was build around it :) that too in the centre of the room. Jokes apart, the base cabinet doesn't provide a few inches gaps to the user for keeping the foot comfortably while using a hand wash. Have you considered the water proofing and maintenance of this unit as what it appears it is wood with laminated top as of now. Do you have a floor plan, as it is a surprising positioning of a hand wash. Thanks, Nitin CORNERSTONE DESIGNS Bangalore

the sink should be at 33" from the floor. your countertop height will depend on if you're using a top mounted or insert sink

Also, I would like more counter space. What size of the sinks should I get? 18 inch? Thank you.

quartz corean white synthetic marble any one as per your budget