[Requesting Help/Advice] Creating buildings and 3D interiors.

Rise

Hello there, i would say i am an intermediate user of 3D modelling being able to create a pretty wide range of assets, recently i have decided to attempt creating a pretty basic game using semi photo realistic game assets/ textures. Although i would take any advice and help in the creation of anything from Plant Life to Animals, however where i am truly having some difficulty is in the creation and workflow of Interiors as well as the exteriors of buildings. 

This simple game i plan on creating will most likely be a choice based RPG style game where the scenes are pre made renders, probably being used in an engine such as Ren'py or Unity. 

Any help and direction you can show me, any material you can point me towards as well as any tips you can share that will help me in the creation of these 3D scenes would be fantastic, especially if it relates to the creation of Interiors and exteriors of buildings as well as different workflows would be very much appreciated. 

Not sure if it makes any difference but i am currently using the latest version of Blender, i seem to be enjoying it a lot however i am not sure if this could possibly impact me in the future, again any advice would be appreciated. 

Thanks for any replies i may get 
- Rise

Rise

I started my learning process by hunting down some places where i could find some Architectural blueprints as well as pictures of the exterior of what the building should look like. (This was an undertaking in of itself) I found these blueprints of a pretty cool luxurious cabin. 

 
This didn't give me much trouble as i was able to follow the dimensions and make everything to scale as well as figuring out how big to make the doorways etc. 

However i have started to encounter difficulties when trying to create the roof of this cabin, this cabin is a (In my opinion) a pretty complicated shape and me lacking experience in this field is making me have a bit of trouble. 

 
I cant seem to figure out a way of making the different shapes and angles intersect in a way that is neat from the inside, this particular structure is meant to have a loft and therefore simply ramming the pieces inside of each other isnt really an option, if anyone knows anywhere i can find some help and information about the creation of structures such as these or any help you yourself could provide it would be very much appreciated. 
Many thanks
- Rise

sacboi

If Unity is a targeted IDE option, then I'd suggest reviewing the Manual/Documentation especially for art asset best practices, also their forums have further additional relevant info and as for buildings plus interior environments I'd recommend a modular alongside interior level workflows respectively, since un-optimised assets will usually have a tendency effecting performance due to processing issues at runtime which of course is dependant on the size and complexity of your game as well.