What do you consider a fair tip for a pizza delivery driver?

I am currently delivering pizza part time for some extra cash since I am dealing with nonsense in my life at this time , and I have been receiving some really nice tips From people but of course I run into cheap asses as well. When I order pizza for myself I usually tip the driver 5 or more dollars depending on where they are coming from , if they are close
To my house I usually give 5 but if they are coming far I will slip them 10 bucks , some of my customers tip me 20 to 30 bucks depending on their order and then I got customers that tip a dollar or 2 because they are cheap asses , with the price of gas prices today it pisses me off that people are that cheap. It’s like don’t order food for delivery if you can’t tip your driver decent. But it is what it is I guess.
What do you consider a fair tip for a pizza delivery driver?
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