Hey - I really dig the nice serene and balanced scene you have as base set-up.
These are just the ways I’d go about doing it, please take on board whatever you feel is necessary.
Determine how realistic you want this to be - you may have to use an external renderer and get the instructions for some like YAFRAY.
If you want to go low poly, less time approach, existing blender renderer . . .
Regarding the texturing - personally I prefer the textures to do most of the ground work. You can UV-unwrap (please get tutorials on this off the 'net - some really easy to follow ones out there) it and edit the textures in some program like GIMP. To get it really detailed - you can go the further mile and add in the spec’s and bump mapping etc. My own lazy way for this is to get an existing material library (Meta-Androcto’s library is a good resource . . . and I’m afraid I haven’t spelled this correctly) and simply tweak the Maps to a jpeg that I use . . . since the settings are already to some extent what I want.
For light, I prefer several (like 3 plus) and with the shadows turned off for some of these. I also use the emit button in the textures stage to get something I feel is good.
Lastly, since my laptop is quite slow, I’d make the house in one file, sun in another, sea in another and then append all of these into one. OR you can use the layers . . .
Hope this helps - sorry for not going into the details - and hope to see your finished render in due course.