Give him a flat hourly rate Example: $65.00 per hour per man. all you furnish is manpower and hand tools. You furnish any material - mark it up 200%. Keep a detail summary of work description each day and have them sign it approving time and work performed.
Provide them with this and let them mull it over. Be sure to tell them if you are waiting on material to be delivered by them - it's still $65.00 per man per hour because you can't do anything until material is on site.
Personnally, I wouldn't follow up on this after I submitted this type of proposal. Sounds like you could be opening a big can of worms here.
