Plans to transform a vacant space on Center Street in Mentor are moving to the next step.A formal request to amend the previously approved development plan for property behind the former Center Street School is up for miscellaneous review before the Mentor Planning Commission Sept. 6.Chagrin Falls resident and real estate investor Jeff Caimi is proposing a mixed-used development consisting of 17 townhomes in four, three-story buildings with rooftop patios.