I understand why you disagree with my statements. I rebuild the older Toyota's trucks and sell them as a hobby. I know what the stock ones go for in my area, as mentioned I would have asked $3500 for yours, and not likely to have taken less. Unfortunately insurance companies are like cheap car buyers, they will look up the Blue Book price, and tell you the good private party price is all that it is worth. I have had atleast one of these types look at every rig I have sold. I simply tell them go and find one as clean as the one I have for the KBB price and I will sell them mine for the same price, none of them have ever come back.

If you have all of the reciepts of the recent service you might be able to get more from the insurance if your truck meets the level of KBB for a dealership. Dealership prices tend to be $1500-2k over private party adds, if yours would meet this level you might be able to justify to the insurance company that it was worth more. When getting estimates for the repairs you should take it by a dealership and see what they would have considered selling it for. At any rate it is going to be hard to get the insurance company to pony up more money than the KBB for it, they don't have to return you to the exact position you were in prior to the accident, just close, and the $2400 in their opinion is all they have to pay, unless of course you suffered any injuries.

If you want to keep the truck, I would get the insurance company to pay for the amount of damages up to its value, and then fix the truck myself. A used bed shouldn't be more than $1-500, and a new/used rear bumper about $50-200, leaving the rest for paint.

Can you post pictures of the damage, I can't understand why the adjuster would be wanting to total the truck for a rear bumper and quarter panel, or even replacing the bed and painting it.