Neighboring Houses show as Default/Empty

this happened to me as soon as i loaded up businesses and hobbies...

This is happening to me, it's not with specific families, it's with all of Willow Creek, I haven't installed the new pack for fear of making things worse, and I think I did well because people keeps saying that now corruption is spreading to other worlds faster, considering that it uses the same system as for rent, the truth is I'm not surprised.

The truth is that a game in which we have spent so much money I think can afford to fix these errors that can bring down the game completely.

Unfortunately after downloading the new Hobbies/Business DLC, clicking a lot in the following worlds: Willow Creek, Oasis, and New Crest made the lots go back to the default lot and/or disappeared. The whole neighborhood went back to default lots. I had to go back to an older save file and started to delete more lots (I'm left with 5 rental properties) in order to play the new Hobbies DLC. I have all available DLC's for the game. Definitely a memory issue. I'm afraid to add more lots in Nordhaven because it will start to corrupt my other lots in my other worlds. 

Keep in mind, moving the sims out of the lot or replacing a house/rental lot will still cause the corruption later. There's no temporary fix

EA_Cade 
Here - another video with this problem
Plus when this bug appear - you don't have arrow to switch levels in "for rent" lots 

https://www.youtube.com/watch?v=2Aov93wL1jw 

Where do we upload the savegame?

I'm having this issue as well. I've been building my own save file and the surrounding community lots in Oasis Springs revert to their default lots but look fine on the world map. I've put a lot of work into the save so I just can't transfer it. I'm hoping that if I stop playing the save for a while, EA can fix it in the mean time.

I play on PC with mods and cc and the workaround doesn't work bc it happens also on community lots.

After my investigation, it turns out that "for rent" lots work like cloned (which makes sense), but they take up a lot of space for the game cache. What lots + a many of families cause the background to be set to default. Even adding a new plot that is not "for rent" can cause this problem (I posted a video on YT below) because the "cache" is full.

I even test that TOOLS maybe make problems - no it is't. 
With or without mods results is the same - you have more (not default) lots on save (for rent and penthouses are heavier) and families - default backgroud will be appear.

I REMIND you that the NEW DLC introduces a NEW world (and a new type of lots), which can result in you having this error right after installing the new EP because the cache will fill up.
I had it after installing Lovestruck when release (L&D start on new save)
So EA, please fix that, add more "memory" - With each new add-on the game runs worse and worse.
If you have the courage to sell "Get to work 2.0" at least give us a chance to play it without any problems

I've been experiencing this issue with neighboring houses showing as the lot defaults, but it stopped happening in one save file where I experimented with getting rid of all of my R-rental lots by converting them into other lot types. Once they were gone, I started seeing what was actually built on neighboring lots once again. (I'm not sure if the error went away before I'd completely removed all R-rental units; I'll probably try it again with another save and pay more attention to when it stops happening.)

No mention of that issue in the next Laundry List. I really hope they are working on it and I hope they would communicate on that issue. Adding in more and more worlds and consequently more NPCs and lots and doing nothing about it is a big risk that more and more player will face that issue.