IF the gel-coat is in truly great condition then you can machine wax the outside hull about as fast as you can walk around it. I'd be thinking about doing using the SONAX Cleaner/Wax followed by SONAX Polymer Net Shield. The cleaner/wax would clean the gel-coat and seal it in one step and the SONAX Polymer Net Shield would give some pretty hearty protection for the marine environment.
Nether of the above are "marine" products but I'm pretty confident they would both work on gel-coat. This process would take you about 5-6 hours minimum for a boat that size assuming you knocked out 2' x 2' sections at a time and make 6-8 section passes to each section. These are just guesstimates.
If you started by washing the boat you would have an easy 8 hour day on just the outside.
IF there is ZERO oxidation or any type of water scum staining on the outside of the hull I would be surprised unless it's been out of the water most of it's life. Even still.... you're going to want to use something that offers some cleaning action to "insure" the surface is clean and protected. I'd also recommend the Blackfire One Step. It's a one-step cleaner/wax or AIO for car paint but it should work pretty good on newer gel-coat.
Million ways to skin a cat (sorry PETA, no harm meant).
Doing the inside of the boat, starting with washing her from top to bottom would take a couple of hours minimum. Then polishing the Isinglass, treating the canvas enclosure and "detailing" i.e. machine polishing the inside gel-coat plus cleaning and detailing the electronics, etc, would take 4 to 5 hours or more. Just depends on how complicated everything is...
I'd figure out what you want to make per hour and then estimate the hours and add some cushion then give him a price.
For example, if you want to make around $75.00 per hour, guestimate the number of hours for the outside and give him a prices. Then estimate the number of hours for the inside and give him a price. There's no way you can do this boat in one day by yourself so you NEED to break it down by the day, not the job.
Off the top of my head I would say a low of $800.00 for the outside. In order to figure the inside price you need more information. For example does he want the canvas cleaned and protected with a product like RaggTopp?
