AP has a set value .. that set value is adjusted by prestige and also adjusted by preferences. So the APs are not the multiplier .. Prestige and Preferences are the multiplier.
So, (as an example, I DON"T know the exact factors) ... Let's say 1 AP has an absolute value of 10 for recruiting effort.
If you had max prestige, you would get the full 10 points. IF you have a B prestige (if A+ is 100% and B is 80%) then you would get 8 points for your AP instead of 10 points. Same with Preferences. They have some percentage they add for or take away from the standard value for 10 based on good or bad preferences.
But Prestige and Preferences are also multipliers (or used to increase or decrease) the Effort Points for HV and CV .. if HV is 200 points as the baseline score, it might be 160 points (again my 80% .. which is JUST A GUESS) for a B prestige and 200 points for A+ prestige. It is then also modified based on preferences.
So each individual item is modified, on the turn you input it, for prestige and for preferences. Which is why you want GOOD for playing time as soon as possible, as it makes every other effort you do worth more.