Based on your summary, I am not sure that you need a Will OR Trust, strictly speaking. You need to check with a Montana estate planning attorney before deciding on anything, for sure.
The assets that you have mentioned can all be disbursed by way of beneficiary designations. This eliminates the need for probate, and hence, eliminates the need for a Will. Whether or not a Trust would be useful in your situation depends on your other planning objectives. Most assets with beneficiary designations, such as insurance, can be assigned (or partially assigned), in order to pay for funeral expenses. If you are concerned that your beneficiaries might not follow through, then prepaying your funeral would be a way for you to make sure.
You also need to have a General Durable Power of Attorney for health care and for financial matters. This will insure that you and your finances are taken care of, if you ever become incapacitated. In my opinion, this form or forms is more important to you than a Will or a Trust, because it takes care of YOU, while you are still alive.
An estate planning attorney can answer all of your questions and determine what options are best to achieve your needs.
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This sounds like something you probably should have discussed with your lawyer the first time around. Did you hire a lawyer to prepare your will? If it was a non-lawyer form job, then certainly you should hire a lawyer and incur the reasonable expense to get this set up properly.
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You have had a go on your own, and you are not certain of what you have done. Time to see a a lawyer, or study up so you can be certain. Time is money, take your pick.
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