This answer is accurate for patch 31.2 on the PC.
Completing a mission in stealth adds an EXP bonus of varying size for the next job. (+20% in the example above)
Avoiding a mission for a while adds an EXP bonus to the job. The longer you avoid it, the bigger the bonus, up to a cap of +50%. Doing a mission too often will cause it to get an EXP reduction, which caps at -100%, which stops you from getting EXP from the job completely.
The number of highlighted represents the difficulty, or risk level, of the job. No skulls means normal, one skull means hard, 2 skulls means very hard, 3 skulls means overkill and 4 skulls means death wish. The game also counts how many times you have done a job on a certain difficulty, which is shown as a number below the corresponding skull (hard to death wish in order from left to right). The selected job's difficulty is also written to on the right side of the skulls.
Pay grade, day rate and contract pay have since been scrapped and combined into a new job payout value
As you can see in the , lists the base payout you are guaranteed to get for completing the job1. It also separates the base amount for doing the job on normal and the additional reward from increased risk. Bags and instant cash are added to this amount at the end of the job, in debriefing.
Lists the experience you will gain for completing the mission. White number is the job's base amount on normal, yellow number is the EXP added by the risk level, blue number is the stealth bonus from last contract and the orange number is the EXP bonus for avoiding the job for a while (and red would be EXP reduction for doing the job too often). It also tells you how close to a level up it will get you (blue percentage in parentheses).
This is the result of the calculation (base + risk) in Job Payout, and represents the same thing.
Note that this screenshot is from a different mission than the briefing screenshot
Same as Job Payout and Experience in the briefing screen.
Crew Alive Bonus
If playing with others, and more than one is alive at the end of the job, you will get a bonus to the total payout. The more people survive, the more money you earn.
Bag Loot Items
Money earned from looted bags.
Money earned from clutter and small items picked up during the job. This includes things like single pieces of jewellery, single gold bars, rings, etc. Everything you just press to loot instead of carrying it to the loot drop-off point.
Money earned to the offshore account. This is 80% of the total cash2. This money can be used to buy contracts and advance infamy, when you reach level 100. Sometimes you can also use this to buy instant paydays to earn masks, mods, etc.
Earned money that you can spend. This is 20% of the total cash2 and can be used for assets, mods, weapons, skills, etc.
1Killed civilians are immediately deducted from your spending cash as you kill them and do not affect the job payout. As a result, killing civilians has no penalty if you have $0 spending cash when starting a job.
2Contract Pay + Crew Alive Bonus + Bag Loot Items + Instant Cash