The storehouse whose main purpose normally was keeping reserves of food, is situated very close to the main house. However, at Glein the shop and post office occupied one end of this building, and the interior of the old general store is still intact. The main house, erected in 1880, was actually not a new building, but moved from Rana where it had also been a house.

In Nordland trade was heavily regulated during the first half of the 19th century. An act introducing freer trade slowly worked its way through parliament during the 1850s and was finally introduced in 1868. This gave the "fogd" (civil servant with responsibility for policing, prosecution and tax collection at county level) the right to issue business licenses to citizens who fulfilled certain criteria. In the county of Nordland the number of traders increased from 163 in 1860 to 445 in 1880 and it went on growing towards the turn of the century. During this boom period business picked up at Glein too. During the 1850s and 1860s Peder C. Glein ran the farm, the trading post and the local shipping agency. However, he sold both the farm and the other businesses to Andreas Pettersen who came from Tjøtta (an island further south). For a while he went on running the shop and the post office at the farm, but moved them to new premises at Innersida by Gleinsvågen. Here he also built a bakery, a warehouse and a boathouse for larger vessels. During the summer Pettersen would take part in the herring season and he would buy cod from Lofoten during the winter. In spring clipfish was prepared and dried on the rocks by Gleinsvågen.

On the island of Dønna there were in the year 1900 trading posts at Glein, Aaker (Stavseng), Nordøvaagen and Hovseng.