I guess I may be in the minority then. I just think about what rooms a home needs and try to fit it all in.
One time I made a starter home that actually had and attached one car garage and a basement and managed to keep it just under 16k. The stairs to the basement had no walls or even a railing around them but hey, they were there. lol
I actually had a lot of fun playing that one. I moved in a brand new sim who made her fortune painting and the stairs to the basement found themselves with railings rather quickly, walls soon after.
In fact continually renovating this home as she got richer and richer self imployed as a painter the house didn't get bigger but it got much more atractive. So much so I never once felt compelled to move her into a bigger house anywhere even after she had several million simoleans. She was quite comfortable there.
Fixeruppers are great.
Anyway. I never once tried looking online for floor plans for inspiration. Everything I build (for better or for worse) is born in my head and in my head alone.
EDIT: Just took some before and after screenshots of that starter home. Purchase price - $15,984
That's basically The Monotone at 72 Water Lily Way modified with an attached 1 car garage and a basement.
As you can see it's pretty bare inside. There aren't even any lights. lol
Now here's what it looked like after a new budding artist moved in and made her fortune self employed as an artist.
And here's the small but pleasent backyard.