1. Do I need to have an attorney review and make changes to the the contract before using it the first time?
It is up to you, wouldn't hurt, but also depends on your budget. With attorney's, they all eat. Take them to lunch, lunch is cheaper than retainers :)
2. When do you open escrow? When my offer is accepted or after I have it assigned?
I let the end user open escrow. They will be buying it anyways.
3. How do you determine your assignment fee?
I determine mine based on what the market will bear and how good of a deal it is based on the market and what the end investor wants. I have assigned for as little as $1,000 and as high as $30,000. The latter was because I got such a great deal and then shopped it to multiple investors.
4. When is your fee due? Upon assignment or when escrow closes? I am asking to be paid upon assignment.
Either or. I shoot for as soon as possible. Some of it will depend on how you structure the assignment. If you go the attorney route, they can help, or title company.
5. How do you collect your fee? Cashier's check, wired funds, ... ?
Cash is King. But any form outside of a personal check :)
6. Do you ever ask the investor to put up the Earnest Money Deposit ?
I do not. But it doesn't mean you can't. Most the time, I have found, the investor will not, unless they are buying the deal. Since you have to secure the property before assigning it, you will most likely be putting down the earnest. Plus, most investors will not put down earnest, unless the contract is in their name so they can have control of their funds.
Good Luck