MapQuest seems like it might be 6x more expensive than the others listed in the post, if "transactions" are the same concept: https://developer.mapquest.com/plans ($100 for 30,000 transactions)
(transactions aren't defined anywhere I can easily find tho, so it's possible this isn't correct. but I don't really mind prematurely concluding that they're significantly more expensive if they don't clearly describe their pricing system.)
We just use them on the free tier as well; we used to pay, but I think they upped their free tier a bit and sent us an email saying we didn't have to pay anymore (if I recall correctly). Their API was easy to integrate; haven't had to research mapping companies much recently, so not sure who I would pick now based on more data.
Entirely possible, I've only used their API well inside the free tier, I haven't compared pricing. I presume there's other OSM-compatible service providers with different pricing options as well.
(transactions aren't defined anywhere I can easily find tho, so it's possible this isn't correct. but I don't really mind prematurely concluding that they're significantly more expensive if they don't clearly describe their pricing system.)