Nice Video, but you need to do suspension work. That thing can't seem to decide how it wants to sit. LOL
As for supplying the paint, I don't know any professional painters that will allow you to supply the paint. Also as Jim said, if you already painted it, it probably should be stripped before painting it again. also what you described involves alot of work. The hood, deck lid, and doors would need to come off. You said under the hood, but didn't specify weather it was the underside of the hood, or the engine compartment.
The cost would depend on the labor rate in your area, and the normal going price for a paint job.