We just did a visa run to Vientiane Laos and applied for 60 day tourist visa, it cost us 1,000 baht and they have given us 90 days. Need to make appointment online first. Very easy process providing you have all the paperwork completed.
We have just returned, you will need US$ for most things, some shops will accept their local currency but not all. Take small notes and make sure they are not damaged in any way.