Is it possible to organize Li-River tour and transfers individually in week before Eastern?

Is it possible to take a normal bus in Guilin in the morning to go to Lhi-Pier or will there be no empty seats? Do the river boat cruises sell tickets in advance without standing in line at the pier as I`m handicapped?
How much is the bus resp a taxi from Yangshuo to Guilin? Did anybody use it lately? THANKS!