Looking on the internet deeply has found these results:

house at the sea is the most popular phrase on the web.

house beside the sea 123,500 results on the web	house at the sea 1639,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I do like to beside the sea... He lived in that big house beside the park. You live on the brink of extinction beside the Sea of Decay Did anyone else come into the house besides the paramedics and the police? Plenty of space, beside the sea. Did anyone else come into the house besides the paramedics and the police? If you ask me, I would say it's a natality tourism, which will enrich the tourist offer in our little town, meaning that beside the sun and the sea, we offer much more. Constance now lives in a house beside the main runway at Z�rich airport.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

house beside the sea

123,500 results on the web

house at the sea

1639,000 results on the web

More popular!

I do like to beside the sea...
He lived in that big house beside the park.
You live on the brink of extinction beside the Sea of Decay
Did anyone else come into the house besides the paramedics and the police?
Plenty of space, beside the sea.
Did anyone else come into the house besides the paramedics and the police?
If you ask me, I would say it's a natality tourism, which will enrich the tourist offer in our little town, meaning that beside the sun and the sea, we offer much more.
Constance now lives in a house beside the main runway at Z�rich airport.

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.