Most buyers read the front page of a service contract and the signature block. The rider page, the endorsement, the amendment and the separate sheet stapled to the back are where a contract often changes after you thought the terms were settled. Before you rely on anything the seller described, find every page that modifies the base form.
What a rider or endorsement does
A rider adds, removes or changes a term in the main contract. An endorsement usually works the same way. Some providers attach these at signing, others mail them later, and some post them online and refer to that page inside the contract. The base form may say one thing while a rider says another. Many contracts state which page controls when they conflict, but the wording varies, so look for an order-of-precedence or conflicts clause before you assume either page wins.
Where the extra pages hide
Start with the cover sheet. Look for a page list or form numbers. Check the last page of each form for a revision marking. Then ask whether the copy you are signing is the current version, and whether the form has changed since the sample you reviewed online. A sample posted by a provider may not match the form it hands you at the desk, so compare the two before you pay.
Questions to ask before you sign
Ask the seller to list every form that will be in your file. Ask whether any term on the base form is changed by a rider, and ask for that rider in writing. Ask how the provider sends amendments after the sale, to which address or inbox, and whether you have to accept them. Ask whether a later change can reduce coverage you already bought, and what notice you receive if it does.
Compare the pages, not the pitch
Put the base form and every rider side by side. Mark each term that appears in more than one place. Where two pages disagree, write the conflict in your own words and ask the provider in writing which page it treats as controlling. Keep the complete set in one folder with your purchase paperwork, because a claim is decided against the version the provider holds, and your memory of the sales conversation will not count for much.
When a change arrives later
If a provider sends a new page after you have bought, read it when it arrives. Check the cancellation section, since an unrequested change may affect whether you can cancel and what refund rule applies. Keep the envelope or the email. If the change reduces coverage, ask in writing what it does to repairs already in progress and to repairs you have already paid for.
This site's list of providers that post a sample contract is a reasonable place to start, because a posted sample lets you see the base form and often its common riders before you hand over money. The methodology page explains how we read the published terms, and the tables on this site show the figures each provider prints.