Tips for Ordering Wanli Crab

Choose which kind of Wanli Crab you want to try from the water tanks in the seafood restaurant. Count one crab for each person as a rule-of-thumb.
Have the restaurant people measure the crab and quote the total price of the dish-to-be. Pick a smaller crab if the quoted price exceeds your budget.
Pick the crab recipe you like. Restaurants normally will not charge extra for the ingredients beside the crab itself. However if the crab was brought in to the restaurant from somewhere else then the restaurant will charge extra for preparing the dish.
Wanli Crab prices varied according to seasonality, species, & market supply. Shortage can happen if weather forbids the fishermen to go crabbing.

List of Recommended Wanli Crab Seafood Restaurants (in Chinese).