Very fast. The rooms in both the orphanage and Theo's group mansion began to be furnished. At the orphanage, they already had their own furniture, so although Theo offered to buy it for them, the girls at the orphanage kindly refused. Actually, it wasn't that they didn't like Theo being considerate of them, but they wanted to be able to buy with their own money.
The girls at the orphanage wanted to work hard and pay back Theo for everything he has done for them. It wasn't like Theo didn't understand their way of thinking. So, he didn't say anything and let them do what they thought was best.
It took approximately 2 hours to furnish all their bedrooms, bathrooms, living room, kitchen, etc.
After all that was done, they were in the big living room at Theo and the girl's mansion.