I'm going to try to rekindle this discussion about orthomosaic photo pricing. It is quite interesting how all the articles (there's a couple good ones on Drone Deplo/y people reference a lot) and forum discussions are almost completely void of any discussion in dollar figures. It is much easier to find discussions referencing hourly rate which depending on the job type, area of the world, and pilot experience are typically in the $100-$200/hr range and I'd say the average is closer to $100 ($125?) but that may be skewed due to most people at this early juncture are doing fairly simple stuff like real estate and roofs (non-thermal.)
But as some have touched on here, if you price your jobs out at an hourly rate based on time spent on the job site, you're probably underpricing yourself because of the amount of overhead costs that are not always obvious, especially to those less experienced with running a business. Depreciation and maintenance of equipment, insurance, and travel costs to name a few. In fact, with the traffic being pretty bad in most major American cities these days, travel time is a HUGE one. Your client isn't going to want to pay you $125/hr to sit in traffic for a total of 1.5 hours going to and from their job site, but you will be screwing yourself to pay yourself $0. If the job takes 1.5 hrs onsite at $125/hr but you spend 1.5 hours in the car, you really just GROSSED $62.50/hr then take out all your other overhead and you basically made squat.
How much time did you spend, travel and onsite getting the data for that 40-acre site (including setup/takedown)?
But there's really two parts to the job, the data acquisition, and the data processing. This thread is specifically, how much do you charge for a 40-acre orthophoto, non-survey grade resolution (350ft altitude isn't going to get what is considered survey grade resolution.)
It's funny that no one has even attempted to throw out some ballpark figures on this. For this small growing industry in an anonymous forum, the idea of collusion issues is a bunch of BS.
The way I look at it is you should first get the pricing for a traditional aerial photo (airplane) for that area. The drone will have better resolution but it gives you an idea of what people USED to pay. I'd also talk to some Land Surveying companies and find out what they charge for a basic topographic survey of a 40-acre site on average. Yes the topo is a more complicated product than the orthomosaic but at least it gives you an idea as to whether we are talking $1000 or $5000. Most of us having not worked in either of those two industries have no idea! You could be pricing a product at 1/10th what a larger professional services company would price it at and not even know it!
Let's say you charge $400 for the data acquisition which covers all your time getting the photos including travel time and some overhead. Your processing cost whether you use DroneDeploy or MapsMadeEasy is pretty darn low, like $25 at most I'd say. You're probably looking at a half hour to go through the photos to verify them, stage them for upload, and then examine the finished product. If you're also charging $125/hr for your post processing time, then that's $62.50 + $25 = about $85 in post processing costs. There's also the processing time, which you shouldn't charge for, but the post processing service is sort of like parts for an electrician or plumber. They don't sell you the parts at their cost. So realistically the ortho processing might be something like $100 minimum + $25 per 10 acres = $200 for a 40-acre ortho. But this might be something a airplane pilot charges $5,000 for and a land surveying company would charge $2,000 for! Who knows?
But then you also have project management time. You're not going to get an initial email from the client, reply with a price, get one more email with the go ahead and then the next email you send is a link to the finished product. Most likely you're going to have to have one or more phone conversations, more emails requesting more details or asking further questions, and other hand holding. So figure at least another minimum 0.5 hours of project management time $62.50. These numbers I'm throwing out are all pretty low. In most technical professional services they multiply time 1.5x to account for unforeseen things so they don't lose their shirts.
The other big factor is what value is your service/product providing to the client? Is it key information for a multi-million dollar development project or is it a farmer that just wants to frame a picture of his property on the wall?
So with the numbers I threw out above, they come to about $550 ($300 data acquisition and $250 post processing and project management)
So to answer the OP's original questions, how much to charge for a 40-acre orthophoto, I'd say MINIMUM $550, adjust for competition in your area and how far away the job site is. Realistically, if this job is providing highly valuable data to a mid or large size company, anyone other than a Craigslist Hobbyist is probably going to be charging more.
And note, this is for just an orthphoto at around 5cm/pixel resolution. The OP didn't mention they were doing 3D point clouds (needed for topos) or higher-resolution stuff. That SHOULD cost considerably more than the numbers I'm throwing out.
It still baffles me why discussions and blog articles are so void of any number figures. I really think the main reason is that because the industry is relatively new, most people don't have a clue what things should cost and people are afraid to be chastsized for throwing out stupid numbers. Sort of like the kids in the classroom that don't raise their hands and don't want to get called on by the teacher.