Here is K8MR's description of his seaside operation in the 2015 ARRL International DX Contest (CW):
I operated the ARRL CW DX contest from a roadside park overlooking Sarasota Bay, running QRP with a KX3 and an MFJ telescoping whip planted at the edge of the water. The antenna was extended to a quarter wave for 10-20, and I clipped on a 16 foot extension wire to make it into an Inverted-L on 40. Being next to salt water, it worked very well to the north, very poorly to the south. LU, PY, etc., were tough qsos.
I operated in 3-4 hour stints, tearing down to leave for lunch (and battery recharge), as well as bathroom breaks, as there were no facilities at the park. Setup took perhaps 10 minutes. Depending on the tide, setup/teardown was either in wet sand or a few inches of water.
Great atmosphere watching the sunshine, kayakers, dogs playing in the shallow water, etc. I had several interesting conversations explaining ham radio contesting to other park visitors. And the band were great! With no spotting it was just me and the radio. Finding juicy multipliers with no pileups was fun, especially when they were able to hear and work me. I worked only one other QRP station in my 600 QSOs, GJ2A on 15 meters.
Although I missed operating from a serious, competitive station, waterfront operating in warm Florida weather was certainly worth it compared to the miserable cold weather alternative up north!