How do the concept 'offer', 'acceptance', 'request for information', 'revocation of offer', consideration', 'intention to create legal relations', 'capacity' apply to the following situation? Has a contract been formed? Give your reasons.

1) Albert emails his nephew Nigel, who is 18 years old and has just passed his driving test 'You have always asmired my Aston Martin. I am thinking of selling it and would like to offer it to you first, for 10,000.

2) Nigel replies 'Thank you, I would love to buy your beautiful motor car. But first I need to check I can insure it. Please let me know the year, model and mileage.'

3) Before Albert replies, Nigel notices the car outside Albert's home, with a sign that says 'FOR SALE. Offers in the region of 20,000.'

4) Nigel emails Albert 'No worries uncle, I'll take the car, it's a deal.'