Astoban Investments LLC wants to demolish a Walnut Street building it doesn’t own — and doesn’t yet have a deal to buy — as part of its plan to transform the adjacent Freeman’s auction house property into condos.

In a building-permit application posted to the website of the Philadelphia Historical Commission this week, the developer said it planned to demolish buildings at 1806 Chestnut St. and 112 S. 18th St. in its proposal for a 21-unit condo tower rising over the Freeman’s building at 1810 Chestnut St.

An Astoban affiliate is identified in the application as the owner of the three properties, suggesting that it at least has the properties under contract.

But Robert Schwarz, who owns the 1806 Chestnut St. building, said Thursday that Astoban has no deal to buy it from him, nor any other agreement that would permit its demolition, though he has spoken with the developer.

“I am not saying there might not be a deal,” said Schwarz, who operates his Schwarz Gallery art business out of the property. “But there’s no deal now.”

The proposal is set to be considered Tuesday by the architecture committee of the Philadelphia Historical Commission, which has oversight of the project because the Freeman’s building has been nominated for inclusion on the city’s Historic Register.

Plans at that property, which the auctioneer has said it would soon depart, involve the construction of a 14-story tower that would rise above and behind the facade of the 1820s building.

Eric Leighton, the architect with the Cecil Baker & Partners design firm in charge of the project, acknowledged that his client has no ownership interest in the 1806 Chestnut St. property, but said none was necessary for the “in-concept” application filed with the Historical Commission “to test the waters.”

In-concept applications are advisory only and cannot lead to a building permit, said Paul Chrystie, a spokesperson for the commission.

“The application before the Historical Commission only relates to the 1810 Chestnut St. building,” he said. “The developer may be imagining work to other properties ... but those properties are not designated as historic and the work to them will not be the subject of the Historical Commission’s nonbinding, advisory review.”

A Freeman’s spokesperson did not immediately respond to an email Thursday asking whether there’s a deal for the sale of that building.

It was also unknown whether the developer is in a deal for the 112. S. 18th St. building, home to the underground Franklin Mortgage & Investment Co. cocktail bar. A message left with that building’s owner, Brahin Properties Inc., was not returned.

Astoban managing director Tim Shaaban did not respond to a phone message.

Schwarz said that publicity around Astoban’s proposal to demolish his building has been bad for business.

“I have had multiple colleagues and collectors calling me, being like: ‘You’re closing down? What’s going on?’ ” he said.