Within the last two years, 20 new housing units have opened up downtown, six of which will be showcased on this year's tour.
"There are still a lot of vacancies on the upper floors, but we're making steps in the right direction," he said.
MSO has received grants and private investments and utilized tax incentive programs to reduce the costs of rehabilitation, including the city's Downtown Interest Buy-Down Rehabilitation Loan and enterprise zone tax benefits.
A couple of grants are still in limbo: a $500,000 facade improvement grant for the 300 block of East Main Street and an adaptive re-use grant to rehabilitate property at 117 and 119 E. Main St. Recipients of both grants have not yet been announced.
"It's fun to see the lights come back on in downtown," he said. "These places have been boarded up, closed up. We need to see the lights come on upstairs and see people down there 24 hours a day."
Upstairs/Downtown event information:
• 10 a.m.-3 p.m. Saturday, May 18
• Tickets: $10, can be purchased at Little Bake Shop, Hotel Ottumwa or Main Street Ottumwa
• Buildings on tour will be on each ticket
• Show up at any address to begin the tour
To follow Chelsea Davis on Twitter, head to @ChelseaLeeDavis.