when i add a stop to my ride in uber, how do i know the price of the ride?

Unfortunately, there is not a way to do this in the Uber app. Uber will update the price after you enter your second destination and confirm the itinerary, but there is no way to know how much it will cost beforehand. Hopefully Uber will follow Lyft's footsteps and update their feature, but as of now, there is nothing you can do ahead of time. 

I'm not sure, but one time I added a stop and it added a whole other $10 to my trip, which seemed like a lot and i thought it was on the way. never doing that agian

Apparently Lyft has a feature that automatically adjusts the price of your ride upfront when  you add a stop to your destination. Uber hasn't gotten that far yet. 

Yeah, this is actually not easy on the app

i dont really get this feature either, just doesn't seem necessary to have to add a spot on my trip. if i need to stop at mcdonalds ill take an uber to mcdonalds, relax and eat my food, and call another one when im ready