Someone who works for a commercial insurance company who decides whether or not to accept a proposal for insurance and, if so, on what terms and conditions.
There are many different types of insurance cover available, but some things are just uninsurable. For example, if you are a drug-smuggler, you cannot expect any commercial insurance company to give you cover against the possibility of arrest and detention.
The period in which a quote is valid, i.e. 30 days.