How much is the tow company charging to store your vehicle? If at all possible, move the truck somewhere that doesn't charge a daily fee. The "storage yard" that my motorcycle was moved to after my accident charged $50 a day - which adds up quickly.
Presumably the insurance will pay that fee, but it depends on your policy. If you move it, you're showing good faith & saving yourself possible headaches.
At this time there's not reason to bring a lawyer into things. Work with your agent, if you feel you're treated well & insurance is holding their end of the deal according to the policy, then you save yourself 30%. If the agent is being difficult, you can get a lawyer or request a different agent.
Find a shop that you trust will do a good job and represent you to the agent. Many shops do insurance claims *all* the time. They're going to have relationships with many of the local adjusters & agents. If the initial estimate is too low, it's easier to have the shop communicate with the insurance company rather than you.
Unless you've priced out aftermarket adds in your policy, such as the bumper, you'll get next to nothing for them. I received .25 per dollar spent on aftermarket items in my last motorcycle accident. While 25% doesn't sound too bad for "used" equipment, it barely represents the cost associated with the add ons. You can try to work with the insurance company on this. An agent could say "it's our policy, nothing I can do", but everything is negotiable.