100% Completion
Complete all 90 Story and Procedural missions and you get 68% complete.

Do all 30 car thefts to get an additional 2%.

Do all 50 stunt jumps to get 2.5%.

Collect all 200 pigeons (flying rats) to get 2.5%.

Find all random characters and do their missions to get 5%.

Do all 20 crimes in vigilante to get 2.5%.

Kill all the people on the list (30) to get 2.5%.

Beat friends or computers at every activity to get 5%.

Get all your friend's special abilities and do all their activities. Note: this does not include Dwayne or Roman. You get 10%.