Cheapest is probably ODM.
There will be no consensus on the best. Each solution has pros and cons and the best solution will depend on your personal situation.
Some produce better orthos, others models, others DTM's.
Some are desktop based...
DJI is being driven from the US market. That has been the goal of a segment of the gov't for some time. It has been a pleasure using DJI gear for over 10 years.