Complex sentence: First located at 12 Mechanics Street in New Hope, Pennsylvania, it initially sold vintage toys and novelty items to help support the gallery, but soon the business was fully supported by art sales.
Split into simpler sentences: First located at 12 Mechanics Street in New Hope, Pennsylvania, it initially also sold vintage toys and novelty items to help support the gallery part of the business. Before long, though, the business was fully supported by art sales.