In 1991, LEGO released 3 Town Vehicles sets, all of these sets have been retired. For that year, the total price of all retail sets cost $25, today those sets are valued around $259, a growth of 946%.
Most valuable 1991 LEGO Town Vehicles set
6352 Cargomaster Crane $149.75
Most owned 1991 Town Vehicles set
6669 Diesel Daredevil
3 sets

6352 Cargomaster Crane

Theme / Subtheme Town / Vehicles
Year 1991
Pieces / Minifigs 140 / 1
Availability Retired
6352 LEGO Cargomaster Crane
Retail $12.75
Value $149.75
Growth  +1074.5%
Annual growth 7.2%

6510 Mud Runner

Theme / Subtheme Town / Vehicles
Year 1991
Pieces / Minifigs 34 / 1
Availability Retired
6510 LEGO Mud Runner
Retail $3.25
Value $31.89
Growth  +881.2%
Annual growth 4.3%

6669 Diesel Daredevil

Theme / Subtheme Town / Vehicles
Year 1991
Pieces / Minifigs 90 / 1
Availability Retired
6669 LEGO Diesel Daredevil
Retail $8.75
Value $77.14
Growth  +781.6%
Annual growth 5.6%