Hi, I'm looking for transport information on how best to reasch Baise from either Guilin or Nanning.

Nanning city is much closer from your destination.
At Nanning Langdong Bus Station, there are many buses to get there from 08:00 to 22:10 and the bus fare is CNY90 per person.

From Guilin General Bus Station, you can take the direct bus there, but I heard there are only two direct coaches in service.