I need a tolbox but have got no experience with one. Can you suggest what things to consider before I choose one? Some examples will be very helpful.
Some aspects you should consider would be:
Make sure it's not too big for you to be able to move.
Even if you're planning on just using it for storage, you will need to move it from time to time. So you'll need to make sure you can still lift it when it's full. Even if it has wheels there will be times you'll need to move it upstairs for example.
If you're moving it a lot then choose one that's just big enough to hold the tools you need. That way you won't be tempted to overfill it. You'll also need to ensure that it will fit in your vehicle.