First, I'm not an attorney and this isn't legal advice.
A will basically says when you die, this is how you want things to go.
A trust is basically a separate entity, which takes ownership/possession of those items, which has a manager (the trustee), for the people who get the stuff (beneficiaries). The trust actually owns/possess those items, so they're not 'yours' anymore...they're being held for you, until you can't manage them anymore (usually death, or incapacitation), at which point the assigned successor trustee manages the items for the beneficiaries. If it's in the benefit of the beneficiaries to sell/liquidate the assets, the trustee can do that, depending on how the trust is set up.
There are also different legal requirements in each state, and a difference between a revocable and non-revocable trust.
There are situations where the assets of a trust can be liquidated to satisfy debts of a beneficiary. so while a trust is a great tool, it's not always the best tool. Also, if something owned by the trust incurs a liability, eg you put a car in a trust and get into a wreck, or you have a house in the trust and someone slips on your steps and sues, generally speaking the assets in that trust are also at risk of being liquidated to satisfy liabilities of the trust.
Also, when it comes to tangible property, from my experience, most will need to be transferred into the name of the trust, since the trust owns the property, not you... and all the associated fees, taxes, etc that come with it. For a gun, or cash, it's pretty simple. Write it down and it's done. For a car, house, etc. there's paperwork and titles that have to be dealt with.