Complex sentence: Commercial vehicle activity was increasing with the first bus being made in 1903 and fire engine in 1908 and the cars took second place and it is doubtful if any were made after about 1915.
Split into simpler sentences: Commercial vehicle activity was increasing with the first bus being made in 1903 and fire engine in 1908. Cars soon took second place and it is doubtful if any were made after about 1915.