The efficiency of the project would be raised considerably. With the current way of doing things you would have 2 people operating equipment that costs $40K and take on average 10-15 min to set 1 point. My cost for the system right now is $3K and only paying one person to do the job, giving me more crew to stake more sites.
The problem is, you're asking for military precision, and you're not gonna get that on an aircraft of any kind, for less than that $50K you're trying to beat. I don't even think you can get that with $50K - trust me, I've worked in aerospace with this kind of stuff, and while there are COTS LPS systems you could use, they aren't below your price point. This is not something drones are going to be good for. Drones are good at covering large areas quickly - they are not good at precision stuff.
Furthermore, a multi-copter of any kind is never going to be stable enough for surveying in the traditional sense. A multi-copter might be useful for laser surveying where you don't need lots of accuracy but need to get the general lay of a large area. Trust me on that - I fly quad copters and hexcopters every day. I have a friend who does aerial photos as sort of a business, and guess what his favorite aircraft is? 30-foot pole.