Yangshuo has a great choice of hotels to suit every taste. The prices in most cases are below $100 per night. There are no premium rooms for $1000+. And even Four Seasons is just a faked copy of the original brand. Find hotels in Yangshuo
How to get there 
Fly to Guilin International Airport (KWL)
. The cheapest international flights are from Kuala Lumpur and from Singapore.
It is the best to move directly from the airport to Yangshuo, as Guilin itself is not very interesting:
1. Taxi is fast, but expensive. It is best to ask your hotel to prebook a taxi for you.
2. Bus. Sometimes you have to wait until the bus is full, but overall it's quite acceptable way of transportation. If for some reason you couldn't catch a direct bus from the airport to Yangshuo, just get to Guilin first and next change a bus to get to Yangshuo.
The best is to walk on your own around the Yangshuo, as taxi is pricy in town, while distances are small. Rent a bicycle to visit the surroundings. Find flights to Yangshuo
When to go 
There's no many rains in Guilin from August to March. However, warm weather is from April to November.
So the best time for a holiday in Yangshuo is a period from late August to November. The only suitable spring month is March (but it's not perfect anyway).
As for the beach vacation, the only good time is late August to early September.
Water temperature, C
Wind speed, meter/sec