Hi guys
yes you can apply off-sure (uk eg) and it costs around £200, to extend.
recommend doing it yourself - it's silly paying an agent to do it.
Just upload all your evidence and hit submit,
we had to redo the Medicals as it was 12 months over.
We heard back in about 3 weeks.
(If you miss something - the agent will let you know by email too.)
Honestly, don't pay an agent to do it if it costs so little to apply (minus the medicals! )