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@HKH191 When I was originally playing around with this mod I noticed if I used it during the storyline there were often props missing in story locations, like Franklins Aunts place Franklin's bedroom was stripped bare like he didn't live there anymore, in Floyd's apartments there was either a missing picture frame in the lounge or it was constantly there even when planning the heist, Michaels house had missing furniture like the bed, his wardrobe, most of the stuff in Jimmy's room, it was little things here and there, including no Impotent Rage statue in Trevor's trailer. However using this mod after finishing the storyline a lot of those missing prop issues seemed to either clear up or no longer matter, Michaels place seemed to clear up after all his family drama, Franklin's Aunt's place isn't a safehouse anymore, neither is Floyd's (now a crime scene) and Trevor has a nice clean trailer thanks to Mrs Madrazzo, so maybe it's a gamestate issue concerning those interiors, just spitballing, but hopefully it helps, anyway Trevors got some Meth runs to do so thanks for the mods and the continued work. :)

Have switched back to the original SPA, this version seems incomplete, seemingly caused a few more errors the longer time went on, like many freeroam activities weren't working for some reason and removing this seemed to fix that problem, so to with pay 'n sprays. the original SPA might be abandoned but it seems to function better, except stilt house of course which cause some weird visual interactions, plus some of the apartments don't load properly, but I can just turn off those features and it seems to run much better in the long term than SPA II does, tbh not sure what the advantage is to restarting the entire project, I'm sure you had your reasons but as it stands this isn't really a replacement for the original SPA, more like an alpha release of a new architecture, good luck with it, I'll check back every now and then for updates, but for now I'm back on the original release.

Ideally a setting just to "Enable individual ownership" would be great, letting people keep it as is or activate individual ownership, though since most modders use the mods for single player then I'm pretty sure that individual ownership would be much appreciated.

After a bit of work I have got this working, I had to turn off the MOC in Enable All Interiors and remove the code relating to it from the bottom of the settings file, install Open Command Centre Interiors, and set the internal color scheme to one of the white color ones. I now have a working MOC and everything else, however there are a couple of bugs:
The first is that the dark colors for the MOC are missing textures for the doors, resulting in ugly bright green or blue doors.
The second is that often many markers will vanish from the map, like Pay 'N Sprays and even the safehouse markers, this usually happens after purchasing or resetting things.

One final question, is it possible to lock the businesses to a particular player character? So if you buy the business as Trevor then Trevor is the owner? I ask because I bought a business as Trevor first, then switched to Franklin and bought the Biker business, but when selling only Trevor has ownership yet I can do everything else as Franklin. The SPA II mod has a way to set owned properties to each player but only deals with safehouses, not sure but maybe you can speak to them and see if you can incorporate it in this too? Would be a great Quality of Life addition. :)

@Johnsel You should only have to update the SPAII.dll and SPII.pdb file in the scripts directory to be honest, but it's worth just backing up those folders, then installing all of the update and just copying your backups back in, this will overite any duplicate files but also leave all the new ones from the update where they should be. :)

@Johnsel No worries, don't worry about the .exe file, it's just a GUI to change the settings from outside the game, the data it uses is stored in those files I mentioned.

In regards to performance issues, it happens with Enable All Interiors too, it's a game issue, not a mod issue and the solution is to turn off interiors you don't intend to use or don't need, while it'd be awesome to be able to own everything, the game wasn't really setup for it, not the single player game anyway, so a bit of compromise may be necessary if people are taking a severe performance hit.

@Johnsel Since you keep asking without just looking;

You need to backup the "Garages" Folder in the SPA II folder (Grand Theft Auto V/Scripts/SPA II/Garages)
and the "modconfig.ini" file in the SPA II folder (Grand Theft Auto V/Scripts/SPA II/).

Then install the updated version, and copy your backups back to where they came from after that and it will restore all your garages and playerowned settings, I will not garauntee this will work perfectly though as updates to the mod may have changed the way data is stored in the relevant .xml and .ini files, but it should work.

In future, rather than just repeating a question over and over try investigating the issue a little bit, this took me about 3 minutes to work out and most of that time was spent waiting for the game to load so I could save a vehicle in a specific garage and then work out where the values were stored for property ownership, it wasn't really hard and there are also other people who have asked this question, so looking back through the comments a bit could have helped you as well.

@ImNotMentaL Sorry to write books in your mod comments, however if you think it'll help then feel free to pin or butcher my comments to add to your description, maybe it'll help some of the newbie modders sort out their problems and enjoy your mod as much as I am. :)

BTW that last comment was made after spending the past week getting all these mods to run flawlessly together (not every minute every day of course, had Christmas in there too, plus I added a shite load of cars to the game, they seem to install with relatively little fuss at least), I have absolutely no problems, no random crashes, no unsaved assets, everything exactly as it should have been if Rockstar didn't abandon their single player game. ;)

Note: You don't HAVE to install the trainer but I highly recommend you do, it has some amazing QOL features in it that can actually make the game more challenging, along with some fun features for when you get bored, like increasing your car weight so you can play Car Pinball and send any vehicle flying through the air with a tiny bump, surprisingly entertaining and I lost 3 hours of my life to that activity before reverting the setting and carrying on with my game. lol ;)