If you're travelling to the United States for a holiday or a limited number of other activities you need to apply for a visa waiver through the Electronic System for Travel Authorization (ESTA) system. I had to apply for a visa waiver last night and discovered, the hard way, that there are businesses out there that make the cost of a ESTA far higher without adding any value. In other words, beware the ESTA rip-off.
Like many people, I simply hit Google, searched for ESTA, and clicked the first link I saw that wasn't an ad. It turns out I clicked on the very official looking and sounding estasystem.com. It's one of several sites, I later discovered, that provide a pretty front-end to the service offered by US Customs and Border Protection.
The offical site for applying for an ESTA is https://esta.cbp.dhs.gov/esta/application.html.
The rip-off comes in the fees. The official fee for an ESTA is US$14.00. But these unofficial sites bump that up to US$84.00.
What I realised after the fact was that the unofficial sites call themselves "Visa assistance services". Other than making the form you need to fill in a little nicer, these "visa assistance services" don't actually do anything to help you along the way.
If you need to apply for a visa or a waiver for any country, start by going to the official website, paying close attention to ensure you don't end up paying excessive and unnecessary fees.