With a luxury apartment tower near Millennium Park already on the market, John Buck decided to sell another in River North as well.

The Chicago-based development company has hired Jones Lang LaSalle to sell 3Eleven, a 25-story building with 245 apartments at 311 W. Illinois St. that opened in 2018. Buck is looking for a buyer at what should be a good moment, with downtown rents at record highs. But the downtown multifamily investment market is sluggish amid rising interest rates and a general investor aversion to tall buildings in the city.

That hasn’t stopped Buck, who is in the process of selling Mila Chicago, a 42-story tower at 201 N. Garland Court. A buyer has agreed to buy the 402-unit building, according to the website of the brokerage selling it, Walker & Dunlop, but it’s unclear when the deal will close. The status of the property, “under agreement”, has not changed for months on Walker & Dunlop’s website.

Representatives for Walker & Dunlop did not respond to requests for comment. A rep for Buck declined to comment.

It’s been a slow year for major downtown apartment sales, with only three topping $100 million so far. In the most recent major transaction, Morguard, a Canadian investor, paid $133 million for Echelon Chicago, a 350-unit apartment building in the Fulton River district.

Brokers say many institutional investors have decided to stay away from the downtown apartment market, worried about the prospect of higher property taxes, crime and a perceived anti-business attitude in the within the municipal government.

Rising property taxes are a risk after Cook County Assessor Fritz Kaegi raised assessments for downtown buildings in 2021. Kaegi’s office valued 3Eleven at $73.1 million, in 24% increase compared to 2020.

The county has yet to calculate or send final tax bills this year, leaving many homeowners wondering how high they will be. Some investors wait for new acquisitions at least until they find out, brokers say.

It’s up to JLL to find those still excited about downtown Chicago. The company barely contains its enthusiasm for 3Eleven in a marketing brochure for the property.

“Residents of this magnificent building enjoy an ideal lifestyle to live, work and play, leading to a new state-of-the-art office development and a thriving River North location,” the brochure states. “Surrounded by vibrant nightlife, Chicago’s best dining scene, and the city’s top employers, these tenants of choice are drawn to having the best of Chicago right on their doorstep.”

The brochure does not include an asking price for the building, which is 95% occupied. Monthly rents range from $2,394 for a studio to $5,872 for a three-bedroom unit, according to the brochure.

In addition to 3Eleven and Mila, Buck also owns Porte, a 586-unit apartment complex in the West Loop, in a joint venture with Lendlease. On the office front, the developer recently hired JLL to sell a 38-story office building at 33 N. LaSalle St. Buck in June also unveiled plans for a twin-tower office project next to the Kennedy Highway in the West Loop.