Make sure to get clear information on price, delivery, payment and other terms of purchase.
Read the vendor's policy for handling and protecting your personal data and payment information.
You are best protected if you can pay with a debit or credit card.
Check your cancellation rights.
Make sure the vendor informs you of your rights in case of defects in the purchased item.
Make sure information is easily available on the name of the shop, its street address and other contact information, for instance e-mail address and telephone number.
Read the vendor's policy for handling and protecting your personal data and payment information.
Make sure that you have received all the information you need about the product/service you are considering purchasing.