Bundling auto insurance with your renters insurance may save you money in many cases. However, sometimes, the bundle quotes might not be cheaper than the policy you get after you simply switch to another insurance carrier. Even if the quotes are cheaper, don't assume you're getting a bargain. If you transfer insurance policies, be sure you don't lose any coverage and do the research!
The information in this answer is general in nature and is not legal or insurance advice for your specific situation. Policy language varies carrier by carrier; your declarations page is the final word. If you're unsure, call your agent before you need to file.