When I setted under the residents in game it just vanished after it is built, and even when I see underneath ground (by typing B and V) I couldn't find it anywhere.

I have 2 questions.
1. How can I connect this parking lot to surface roads?
2. Can I stack these parking lots?
In my real life, My apartment complex has a 3-floored underground parking lots whose width is equal to the entire apartment complex.

Thx @Erke, yes I was thinking about such version but then realized it wouldn't fit every building like the current model. Moreover, there was no makr for cars entrance when I was doing this.
If You have skills to make models, there is a better way - you can make a small garage drive prop and use it in the game wherever you want. The second option is to add such an entry when designing the building mesh (more difficult approach).

Hi this is by far the most professional approach for underground parking I've seen so far...

I will be using this along with tmpe advanced parking, so I may have to disable the visitor capacity and/or atraction via rico, so It doesn't need parking itself...

Would you ever consider a version with a tiny road entrance so we can actually see cars going in and out?

@alborzka, never done RICO asset but maybe You can do it easier. BloodyPenguin have alot mods helping with assets, one very useful to extract mesh and images: ModTools . With this You can extract asset You need and make it from scratch and You would not need use mine parking to "cheat" ;)

Well, I'm actually not really using this for parking spaces tbh, I'm just using it as a generic sub-building -- to add a sub-building to a pre-existing asset, normally you need a texture and mesh and etc. Your asset solves all that by making it underground, which is why I find it so useful since I don't have those type of skills. So I'm not using this asset to add parking to buildings, but rather just to add the sub-building function to other buildings to configure later with RICO. That's why I was looking for a 1x1 version, so I could add sub-buildings to assets 1x1 and larger without worrying about texture, mesh, etc.

@alborzka, 1x1 will have 2 parking spaces. Will it be useful? I can make such one if its realy needed. Maybe 2x2 will be more useful for smaller buildings. But it will have only 8 parking spaces.
This parking lot is designed for 4x4 and bigger buildings.

Any way there could be a 1x1 version of it, for smaller lots? Scared it may get into trouble with cliffs etc if I use this on buildings smaller than 4x4

@alborzka, this is the purpouse of it :)

Super useful for adding to buildings to provide mixed-use functionality, thank you!

OK, got it! Thanks.

@MajorTom, I do not know how would that work. I've never tried it. Parking is at a depth of about 2.5 meters so it will be hard to connect underground road to it. I do not know how vehicles bevave under ground. Do they have to go to the surface to start the procedure for parking?
Parking is normal building just texture is below grownd so it have to have conection to road normaly.

We can also connect to it with an underground road we design, no?

@shaundoddmusic, my first attempt was to make it with garage entry but I've noticed that it collide with buildings above it. I can make maybe 3 same underground parkings with different entries but I think better to make garage gate in building.

Good stuff. Underground parking is really needed since the new parking AI. You might find this interesting..

http://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=443579877 I'm having problems with it though, it seems to crash the game sometimes, I think. If you view it in asset editor it's similar to your design.

@MajorTom, yes it has 40 parking spaces.

Does this lot fill with cars, or is it just a park?