Price could be anything from a few hundred to tens of thousands depending on what exactly the client wants, do they want a simple catalog type shot or a series showing the internal construction and then the mattress? Do they want advanced lighting techniques that will require a large commercial studio lighting grid and large format scanning back.
The possibilities are endless and so are the prices.
Now for the most important 3 rules of professional photography.
1) Know exactly what the client wants
2) Work out exactly how do deliver what the client wants
3) Cost exactly what it will cost to deliver what the client wants.
Sadly you cannot answer any of the above questions so working out a price is a bit like pi$$ing windward in a typhoon.