To calculate the appropriate amount to give from modifiers, take the sum of all the money gained from modifiers and multiply by the difficulty/2 (round up).
Modifier Bonus=(Total income from modifiers) x (Difficulty/2)
EX: Standard Modifiers- Good Roleplaying, Side quests (3,000), Deadline Difficulty 4, 20,000

500+3,000+3,000=6,500
6,500 x 2= 13,000
Total- 33,000Y

NOTE: Karma is not included as there is already a table for that under the KARMA section of SR4A.

Standard Campaign
Difficulty Total Reward
1 1,000-5,000
2 5,500-8,000
3 8,500-14,000
4 15,000-23,000
5 25,000-35,000
6 40,000-65,000
7+ +15,000 per level

Low BP Campaign
Difficulty Total Reward
1 8,000-12,000
2 14,000-20,000
3 22,000-35,000
4 40,000-60,000
5 73,000-95,000
6 105,000-120,000
7+ +30,000 per level

Reward Modifiers
Modifier Standard Low BP
Roleplaying + or - 500 + or - 1,000
Special Requirements +1,000-2,500 +2,000-5,000
Deadline +3,000 +6,000
Side Quests +1,000-7,000 +2,000-14,000
Other Modifiers Determined by GM