Hi all, I have some questions regarding a little tour that me and my family are going to make from 19th June to 23th June. I'm currently in London and I have an Oyster card. They will arrive at Luton around 19:00 on 19th June. As far as I understand Luton is outside of the Oyster zones and I'll have to buy paper ticket to Luton. What is the best option and cheapest and what tickets should we buy for traveling from Luton to East Croydon - buy paper tickets from the Luton station or to buy buy online tickets beforehand, maybe single or returns (23th June)? Is there any group discount for 4 people? Or if there is a possible combination with the Oyster cards? For the tour in London I'm going to buy them oyster cards and use the PYGo daily capping within zones 1-6 so it should be 11.70 (daily time) per day. The return to Luton, on 23th, may be before 9.30 so the ticket should be peak tariff. Thanks in advance!