What’s is like getting a visa? I believe you can get one at the border if you stay for less than 15 days but I hear different things. Advice would be grand!

I went earlier in the year. You don’t need to get a visa in advance.

Until 30 June 2017 ‘British Citizen’ passport holders travelling for tourism or business can enter Vietnam for up to a maximum of 15 days without a visa. If you have a different type of British nationality – for example ‘British national (overseas)’- you’ll need to get a visa before entering Vietnam.

You must get a visa before you travel to Vietnam if you want to stay for longer than 15 days and/or if you wish to re-enter Vietnam within 30 days of your departure. If you plan to leave Vietnam and re-enter from another country make sure you get a multiple visit visa before travelling. Make sure you know before you travel the type of visa you need for the purpose and duration of your trip. If you’re travelling for business reasons you should contact the relevant Vietnam government department in advance to check whether any licenses are required to carry out your duties.

From fco.gov.uk

I went for a month and got my visa in Bangkok, took two days. The shop I got my plane tickets from sorted it out.

As Gonefishin says, you don’t need one. I’m in Hanoi shortly and had it confirmed by travel company and government site.