You've likely set up a radius around a particular neighborhood as your service area. This is the ideal area of your community that you'd like to accept jobs.
Depending on the style of community you live in, your service radius could be as small as 15 miles or as wide as 45 miles. What happens if someone asks for a job outside your service radius? Should you charge a travel fee?
This is actually a business decision and something to think now. You could have a firm "I only travel to this area" policy or you could be open to traveling for hours. Time and money are not the only factors here, however. You have to first think about the safety of your clients. Are you able to pack up a large quantity of groceries and travel for three hours?
Once you've established this criteria, you can be open to the next question. "If I do accept a job three hours away, would the client be willing to pay for my travel time?" Just because a client appears to have money to spend doesn't mean they're going to pay you $50 or $100 an hour each way to travel to their location.
Before bidding for any job, it's important to ask the location of their event. Is this an area you want to travel to? How much would you charge for the travel time? Will it be per mile or per hour? What happens if the location is only 30 miles away, but it takes three hours to drive there because of heavy traffic?
You are the business owner, so these are decisions you'll need to make or at least think about before the situation arrives.