Complex sentence: Many "Pear Tree Inns" are 1st generation Drury Inns, when the company replaced the older buildings with a new Drury Inn if the company had not torn down the old building they often rebranded the old building as a Pear Tree Inn.
Split into simpler sentences: Many "Pear Tree Inns" are first generation Drury Inns, when the company replaced the older buildings with a new Drury Inn. If the company had not torn down the old building they often rebranded the old building as a Pear Tree Inn.