In 2008, LEGO released 5 Batman sets, all of these sets have been retired. For that year, the total price of all retail sets cost $110, today those sets are valued around $2,047, a growth of 1761%.
Most valuable 2008 LEGO Batman set
7888 The Tumbler Joker's Ice Cream Surprise $803.09
Highest growth 2008 Batman set
7884 Batman's Buggy The Escape of Mr. Freeze +1737.34%
5 sets

7884 Batman's Buggy The Escape of Mr. Freeze

Theme Batman
Year 2008
Pieces / Minifigs 76 / 2
Availability Retired
7884 LEGO Batman's Buggy The Escape of Mr. Freeze
Retail $9.99
Value $183.55
Growth  +1737.3%
Annual growth 8.4%

7885 Robin's Scuba Jet Attack of The Penguin

Theme Batman
Year 2008
Pieces / Minifigs 207 / 2
Availability Retired
7885 LEGO Batman Robin's Scuba Jet Attack of The Penguin
Retail $19.99
Value $244.74
Growth  +1124.3%
Annual growth 8.9%

7886 The Batcycle Harley Quinn's Hammer Truck

Theme Batman
Year 2008
Pieces / Minifigs 267 / 2
Availability Retired
7886 LEGO Batman The Batcycle Harley Quinn's Hammer Truck
Retail $29.99
Value $362.47
Growth  +1108.6%
Annual growth 16.2%

7888 The Tumbler Joker's Ice Cream Surprise

Theme Batman
Year 2008
Pieces / Minifigs 449 / 3
Availability Retired
7888 LEGO Batman The Tumbler Joker's Ice Cream Surprise
Retail $49.99
Value $803.09
Growth  +1506.5%
Annual growth 9.2%

San Diego Comic-Con 2008 Batman and Joker

Theme Batman
Year 2008
Pieces / Minifigs 9 / 2
Availability Retired
LEGO San Diego Comic-Con 2008 Batman and Joker
promotional
Value $452.94
Annual growth 8.8%