I am installing semi-recessed sinks in the powder room and kids bathrooms. I did not realize the builder was going to install vanities that are 36" high. I have children and the extra 4" the sinks will add seem to make them near impossible for them to use without having a stool. What height would be more functional considering our sinks will add 4"? Contractor needs to know ASAP so he can make new vanities! Thanks for the help!