Not sure what you are looking for in that "interior" price. Depending on the level of complication of cushions and curves, that could very well be a fair price. I charge $100/hr and jobs like that become time and materials for the actual cost. Depending on location of the boat, daily travel time is included in that hourly rate as I operate out of my house and not a local marinia yard. So assuming ~$2k in materials, that would be ~40 hours of labor at $100/hr. I would venture to say that is a fair price without actually looking at the job.
