Is your staff fully certified?
This might surprise you, but there are no state regulations on the certification of private school teaching staff, Montessori or not. I have observed in many “upscale” private schools that do not have one person on their staff with a degree in education or anything else. I once visited a school where the only person who had a HIGH SCHOOL diploma was an aide!
The whole “accountability” movement is interesting. Public schools are mandated to have “highly qualified teachers” private schools - who knows? Their whole staff could be Ph. D’s or they all could be mothers who want a cut in tuition for their child.
“What kind of education do your teachers have?”
“What kind of certifications do they have?”
“How do they keep apprised of new educational findings and techniques?”
A school worth its money will have a certified owner, director, principal, and head teachers. Having Montessori certified aides, and specialty staff is wonderful, but not needed.
By the way, don’t accept the word “trained”. If you are told, “We have a fully trained staff.” Repeat your question. "Are your staff members “certified” and with which specific program?" Training can mean anything from actually getting a degree to having read a web page. (I knew a director/owner who told people she was “Austrian trained”. She just seemed to forget to tell people that her “training” was in hotel management! More than that, she had failed all her classes her first year and dropped out! Her extent of Montessori knowledge came from reading one webpage, not even a site, just one page prior to opening her school.)