Hopefully, you are not going to have to get to that question. In fact, the explanation should proceed the presentation of anything that requires your signature within any Real Estate Transaction.
Sometimes, this is not the case. However, there are a few times, more often than not, that you are going to want to ensure you are getting the full monty, when it comes to the explanation of documents.
When you are ready to start signing, request that your Realtor explain to you everything. In addition, there is going to be an inspection period, where you are going to get documents that will be given to you – make sure your agent has reviewed them before hand. You can do this by either asking them, or testing them about specific parts 🙂