I understand from the gov.uk site that fully vaccinated travelers from the US need to book a "Day 2" test prior to arrival in the UK. The https://www.find-travel-test-provider.service.gov.uk/test-type/green list of providers indicates that the prices are very inexpensive, starting from 1.25 GBP, but clicking on the links indicates that the tests are actually 49 GBP and up. I did see one provider covidtestingdirect.com has appointments at the IBIS Heathrow Testing Center for 0.45 GBP. Has anyone used this service? Why pay the extra $66, just for the convenience of getting the test in the mail?