Where is the washer/dryer? and water heater/heat/air. Is there a basement I'm thinking no since its a beach house. Upstairs I like the 2 bedrooms and bath, but for the master way to big for my personal taste. I would put a BATHROOM in the master bedroom. Downstairs seems odd to me I would delete the (what I'm guessing is a couch in the kitchen) and make the dining room more pronounced put a window where the dining room table is at right now. The downstairs bathroom looks out of place. Imagine this I'm watching tv sitting in the upper chair in the living room and I'm hearing the person pooping since the toilet is right next to my ear. Need more info if there is a VIEW from anywhere in the house to place windows accordingly. My crack at it (there could be millions different configurations) Please provide more info and I'll mess around and get you more renders if you like.

I feel option A is better among all, except for the play area because you will be having a whole room downstairs for that. And maybe move the dining a little to the left near the window. You can add a partition to divide the room into living and dining and mount tv on it. Place a storage unit /crockery unit behind the partition. I would still recommend you to opt for the layout shown in the 3d renders as its quiet functional and space is best-made use of. Maybe instead of a tv on the wall, you can use a media partition to divide the living and the dining. The wall along the kitchen can be used to place storage units or shelving. Let me know if you need me to do more 3D layout to help you visualize better.

do you like the location? because that is above all the most important thing. this is a really nice house. adding and removing walls to change the layout seems very possible here. plus it's all one level! win-win! for a temporary solution, your room divider idea sounds great. I love your idea of a bookcase - it will allow partial visual cover while allowing natural light to pass through and not feel so closed in (be sure to securely anchor the end to the wall). if you want to talk impossible, come over to my house. practically no "normal" way to put upper cabinets in the kitchen, small bedrooms, tiny closets. the layout makes it nearly impossible to add or remove walls to change these things. and it's a split level -- four levels! your house seems very workable compared to mine.

If you decide to have the underside of a wall-hung sink visually exposed and want it looking neat, check out Duravit.com. Duravit sells matching pedestals that do get in the way, but also ”siphon covers” that hang on the wall and hide the plumbing behind a porcelain cover that only goes halfway to the floor. They also sell countersinks, in which there is a sink in the middle or one side or the other of a large porcelain countertop, all one piece. A larger, deeper one of these can give the litterbox more cover. You can also get a cheap vanity and cut a cat door in the side of it and use a tray with higher sides to try and capture litter that escapes the box. With two doors on a frameless front, you should be able to pull out the tray to brush it off and wash it. You could also look into furniture pieces that are made to hide the litter box and could look nicer. An activated charcoal filter hung in there and changed regularly could make a cabinet cat box smell better without adding perfume that the cats probably would not like. That works pretty darn well in the Toto deodorizing toilet seats.