After more than 35 years of running her interior design and furniture business in Ann Arbor, Susan Bay plans to close the Bay Design Store on Detroit Street this fall. The decision comes as the building is being sold.

Bay played a pivotal role in redeveloping the 11,000-square-foot building at 617 Detroit St., located just north of downtown. She’s owned the building, formerly a car dealership, since 1995.

She now plans to move to Florida full time to run the existing Bay Design store there.

“With a carefully weighed decision, I decided I need to spend my time down South, where I have a very growing, vibrant business that’s expanding and growing very rapidly. I want to take more time to live down there, go on buying trips and not have to run back and forth between two different states.”

Bay’s decision was prompted when a local investor, Michael Yi — who is represented by Dan Stewart of Sperry Van Ness/Stewart Commercial Group — expressed interest in purchasing the building. Along with the Bay Design Store, the building houses several other office spaces.

Yi owns the Liberty Building on East Liberty Street and Fourth Avenue in downtown Ann Arbor, and a strip center in front of the Walmart store in Ypsilanti Township. He also serves on the Board of Trustees for Pittsfield Township.

The building was listed for sale with Mike Giraud and Randy Maas of Swisher Commercial for $1.735 million. The building’s assessed value for the 2012 tax year was $797,100, making its estimated market value about double that. Yi declined to disclose the purchase price.

Giraud, who called it a “stunning” Ann Arbor building, said he received several offers from people interested in purchasing it. Yi’s offer, he said, “made the most sense to the seller.”

And Yi said it was an opportunity he simply couldn’t pass up.

“It’s a very handsome building,” Yi said. “It’s very well designed and maintained. The landscaping is beautiful and obviously, the number of parking spaces that come with it is great. The other thing is the location; it’s right at the edge of downtown, right by Zingerman’s, the University of Michigan health system and the train station.”

Bay plans to remain in the building until October and she’ll have waves of liquidation sales throughout the summer, beginning with one on June 21.

After Bay closes the Ann Arbor store, the business will still operate full-service out of the Florida location. If there’s a problem with a product, representatives from the manufacturer can come out to help the client, she said.

“We do have a very large interior design business and we have deliveries to fill every day,” she said. “We will continue to do so and follow through and provide services for all our clientele until everyone has their goods.”

Reflecting on her many years in business in Ann Arbor, Bay said she mostly wants to thank her loyal customers and clients.

“We had lots of interesting stories and people passing through the doors,” she said. “I want to thank everyone who has been with us all these years and I hope we’ve been a value to them.”

At least three of her employees also plan to move to Florida to help operate the business there.

Her moving on, she said, also creates a unique opportunity for Yi.

“I think Michael is really going to enjoy being here and having the building,” she said. “It’s not a huge building, but it’s visually beautiful to look at. It’s a landmark building. I hope he has a nice tenure here.”

The building has several available office spaces, including the Bay Design Store space that will be available this fall. Yi and Stewart said they would like to “reposition” the building and make it all office space — potentially for a software or high-tech company.

“A lot of companies in Ann Arbor want to be downtown but need parking,” Yi said. “This would be an ideal location for companies like that.”

Giraud has been working with tenants on the leasing for the building, and recently signed a deal with Synthetic Biologics for the space formerly occupied by Colliers International's Ann Arbor office. Colliers has since moved to South Division Street.

Giraud said he’s been in discussions with three potential tenants for the other spaces.

Yi added: “There’s a lot of interest in these office spaces.”

Lizzy Alfs is a business reporter for AnnArbor.com. Reach her at 734-623-2584 or email her at lizzyalfs@annarbor.com. Follow her on Twitter at http://twitter.com/lizzyalfs.