Limited Power of Attorney
A power of attorney can be a very broad document, granting liberal power to your agent, or it can be a very limiting document, giving your agent the authority to do one specific thing. When you have a single transaction for which you need assistance, you should use a limited power of attorney that clearly identifies the specific transaction.
Example: You have agreed to sell your boat. The buyer will pick it up and pay you on Saturday, but you will be out of town. You could execute a power of attorney to give your friend the authority to sign a bill of sale or any title transfer documents, and to accept payment.