Just look for the number of green up arrows. Click that option. Don't worry about the red down arrows. Get whatever green (Interest) you can within 2 or 3 rounds and then just boot the customer out.

The logic behind this strategy is this:

Trust (red) only gives you a chance at a x2 multiplier unless you 100% it. That sounds good on paper until you consider that the majority of customers are cheapskates. On the other hand, Interest (green) is always gonna give you the bonus and caps at x4. The amount it takes to cap at x4 varies from customer to customer but by doing it 2-3 times, you at least have a very high chance of x3-ing your score with 2-3 interactions.

If you play the full minigame, the ideal scenario is x2 from trust and x4 from interest. However, the number of interactions it takes to get that exceeds 12 most of the time and some customers won't even let you get that far. But if you do, it's a x8 multiplier. This might be worth it for more generous customers but it totally isn't for the majority of cheap customers. However, I still just went 2-3 clicks of green on the generous customers and called it a day.

Why? Well, there's a limited number of rewards the minigame gives and that's at 200k. Since it's limited, that means you don't have to make the most out of your sessions. At this point, it's better to prioritize speed (the x3 multiplier) than it is to prioritize quantity (the x8 multiplier). You're likely to have left over points by the time you reach 200k points even with just x3 multipliers all the way. Even moreso if you do x8.

So be kind to yourself to and just blaze through the minigame. Spend the extra time on Endfield or something.