Ok so we have 68,000 square feet of mowing
Estimated 10,000 sq ft of weed eating
Now is this an area you need to line trim? Like for a culvert?
What about the total linear feet you will need to line trim or edge?
Also will you need to clean the parking lot? Blow it clean of debris?
Think of each service you need to do for this job and list it here. Then estimate the amount of time in man hours it will take for each job.
There still seems to be a lot more we need to nail down here to come to a final $ number.