Dear Richard Campbell,
We just can process 1 year tourist visa for US passport holders only.
For Brintish passport holders, we can process maximum 3 month multiple entry tourist visa. The service fee is 35 USD (not including stamping fee 50 USD).
If you wish to have 1 year multiple entry, you can apply for business visa at our website
You don't need to submit any documents
Kindly apply at this link https://www.vietnam-evisa.org/apply-visa.html