Did any New Testament church have its own building?
No, for the most part the New Testament churches in the Apostolic Age did not have their own buildings; they simply met in homes, which limited them to about 25 or 30 people. Ephesus may have had a separate building, and Corinth might have warranted one, but neither can be proven.
Les explains that the churches Paul wrote to were not humongous congregations of several thousand people. These were congregations that, for the most part, met in homes, which means there could not have been more than 25 or 30 people involved. He thinks maybe the church at Ephesus may have had a separate church building, though he feels that and cannot prove it. And maybe the Corinthians had a large enough congregation to warrant their own building. But whatever there was at Corinth, they ought to have had the same mind, yet they had divisions.