honestly, this is what the term "you get what you pay for" means.
1.50 a foot? thats well under 50% of what most "Professionals" would charge.
I wouoldnt touch it for less than 3.25, but then again I dont leave edger marks, or bugs in the finish LOL
Like it was stated, these things may not buff out, the debris in the finish should, but those edger marks, they require sanding, maybe he plans on taping off individual boards to fix it.
Best of luck to you, please remeber this when you decide to do your next project, Before you pick the lowest bidder. tell your friend this too.