One of the most recent deals came in January when the city’s spending panel signed off on an agreement to sell 17 abandoned houses and one vacant property to a private developer for $18,000, or $1,000 each. About half are along Henneman Avenue, on the block east of the Hoen building. The other half are on Prentiss Place, one block southeast of Hoen. The developer, the Housing Development and Neighborhood Preservation Corp., pledged to spend $3.2 million rehabbing the properties, or about $176,000 apiece.