Iowa Machine Shed Co. has paid $550,000 for a parking lot at 401 E. Grand Ave., where Moline-developer Mike Whalen plans a boutique AC Hotel by Marriott. The deed was signed April 20 and recorded Thursday, according to Polk County land records. As part of an economic development agreement with the city, the proceeds from the sale will be returned to developers of the $18 million project. In addition, developers will receive 80 percent of the tax increment generated by the project for 20 years. The proposed six-story, 100-room hotel will feature underground parking, a rooftop lounge and a small fitness center. The restaurant offering will be limited, designed to encourage “experience-seeking” guests to walk to the area’s restaurants and other amenities, according to a city staff report. It is estimated that the city will collect about $5.7 million in hotel/motel tax over 20 years. The city sought, but did not receive, other proposals for development of the property.