Hamburg based developer Rockstone Real Estate is launching its first construction project in Berlin. The residential building Guardian is designed to offer 134 apartments and 5 commercial units. Most of the the apartment range in size from 40 sqm to 144 sqm. Construction and marketing for the project are to begin within a few days, with completion scheduled for the beginning of 2016. The developer said that about 40 percent of the residential units have already been reserved. The cost of the investment is around €35m.