We can't customize the height I'm sorry to say. We don't provide installation on any of our items. Most customers assemble these items themselves (and the owner's manual is available if you'd like to take a look at it).
If you do hire out assembly, we recommend finding a local handyman through mobile apps like:
Takl, Angieslist, thumbtack and Homeadvisor
We have also found that customers are far more successful at getting more competitive local assembly/installation rates if you join a local facebook classifieds group and create a post like, "Looking for a licensed and insured handyman to assembe my ......." You are likely to get several competitive bids eliminating the middle man.