In addition to above;
Generally there are two components to price, creative fee and usage and then expenses.
I guess you have to take in to account what you are already billing them as a consultant- that might be hourly or per project. Not that that is paying for the photography but there has to be some semblance of value for time only you can work out that seems to make sense for you and the client.
Photographers often try to move away from the day rate or time based model, it is a convenience but it doesn’t really equate to the value of the service. You could spend literally a half hour on location but the prep and your skill and the value within the market for similar products are what tell the real value. We don’t sell by the pound like ground beef
What the “day rate” model can do or the per-shot model is that it can help you structure an estimate so that they can scale up or down depending on how much they have to spend.
(not in this case) but a classic tactic poor clients take is say we have 100 shots how much? and you go through the estimate driving your own price down hoping to get the job and you give them an number and then they say well we only have 10 shots now and now you feel like you have to divide that price by 10!- clearly a manipulation. For corporate clients I tend to give them a per shot rate as a base so that they can understand that if they ask for more it costs more and less is less. And there is only so much you can do in “a day”.
You have specialized skills, and the client already strongly likes your work, which indicates towards a higher fee. However you already have a relationship with the client and a fee structure so that comes in to it as I said above. All of this comprises your creative fee.
Typical creative fees in NYC for architectural or corporate work go from a low of 1-2000 “per day” and up. But as I said, that’s just part of it, accounting for your skill, uniqueness, and possibly some nod towards time but don’t make it about how long you take. You could try a creative fee per pano setup- i.e. per location or maybe per final pano. It could get tricky if they want “variations” on each image.
The second component is Usage, and this is generally the higher part, it accounts for how the client is leveraging your work. You said they wanted “full rights transfer” which I take to mean they want the copyright- so here is my opinion on that.
I’d avoid transfer of copyright. You could give them unlimited rights but it depends if they want exclusivity of usage- meaning you couldn’t also license the work. If you retain copyright and they don’t need exclusivity, or only need it up to a specific time period (embargo) you could then make money licensing the same work later on. However if you transfer copyright then they can basically do whatever they want, and they can also license the work to others and continue to make money from the work. All of this should drive their price up because you have to figure you’ll never make another cent against this work. However retaining copyright and doing non-exclusive after what is called the embargo period means you can lower the price to them for unlimited rights.
Unlimited rights is the Mercedes buy- it includes advertising, editorial, web, social media, printed collateral, display, etc. It would be better to define the use clearly so that you can at least feel that the number you give them is a good reflection of the value they are receiving and leveraging.
Typical unlimited rights usage fees are boilerplate but if you look on Getty Images for example and use their quick calculator you get something like 7-15k per image unlimited exclusive. This might make the jaw drop but without some definition of what they want to do it is hard to say.
Expenses
The gear rental fees you can research locally but high end digital capture goes near 750-1000 rental a day not including specialized lenses or pano heads. You could bill at these rates or a little less but you should bill for gear because others do. It covers depreciation, insurance, wear and tear, etc
Assistants in NYC get about 300+ a day, however you may not need such specialized skill- or perhaps you have a friend you like to work with.
Don’t forget travel expense, scouting fees, insurance, meals.
Its good to feel honored to be asked (like the academy awards) but I would quickly move past that and think about the fairness of the value derived vs. your unique skill, artistry, and honest willingness to do right by your client. Its good that they insist on paying, so get some specfics and if you want come back to this forum and pm me directly and I can give you some basic numbers