Personally depends on when she wants it done for us. If we are slow obviously our rates would go down a little just to bring in some cash. Does look a little large of a job It does not look like anyone has taken care of for over a year.
I would not charge less then $500 for job plus dumping fees. I am thinking from pictures maybe 10-12 hour job.
If during busy time of year it would be more like $900 as we could do other jobs in mean time. How many people were you looking to have on the job? Are they signing on for your maintenance for next year? Lawn service? Treatment? Etc? Could be worth more in future if this is a new owner.