I hadn't been having any low fps problems until I started a new game on a new profile. Then I went back down jerky play and 10 to 20 fps again. But when I started experimenting I realized a couple of things. First, it only happened on the HGTV DLC jobs play through. Second, it was particularly bad any time the player view was of the surrounding neighborhood. Finally, after finishing the job and buying the same HGTV house, play was almost the same as other houses, except when viewing surrounding neighborhood, when my fps would drop to around 35 to 45.

I wondered if this was a my machine thing or if anyone else noticed this too?

I discovered that i get always low fps when:

1. Too many light sources are placed and turned on
2. Too many objects in general are placed
3. Too many workshop objects are used

But you can tackle the light issue by using the ECO options in the settings.

The houses from the Luxury DLC are also more demanding with the fps in general. In my experience more demanding then the HGTV houses.

Fun thing i discovered yesterday: I bought the Hacker Loft again, cleaned it, sold everything in it, and got a stable 60 fps everywhere i look inside there. I guess it's because it's a small space in general, and the outside is also not so big and demanding. Probably one of the best optimized houses in the game currently. If i think about it, the house on the moon should have the same stable fps. With so much empty space around it? ^^

I only spend time in houses without grass. Any house with grass makes my fps drop below 14. Hacker loft is my office because of the lack of grass. Moon is also amazing. I thought the yacht would be good, but if I'm looking towards the town my fps is garbo too. The snowy house is sort of alright, no grass but it's in Luxury so it's not optimized.