Charm, good looks, a winning smile...
Only joking!
When looking for a builder, it's definitely worth considering more than the bottom figure on the quote they present.
You are going to be working with your builder for a long and likely quite stressful time, so you need to find someone you connect with and trust, someone who communicates clearly and doesn't mind explaining when you ask them lots of questions.
Check out some of our guides and tips under the Resources section for more helpful advice.