NOTE: I'm using Poser 4!

Hey,
I'm sort of a newb at modeling, though I've been using Poser 4 for a while, so I got a good idea of what the program can do. Unfortunately, I cannot really find any hospital interiors on the net that reach my expectations, so I'm going to give it a go myself. I want this thing to be as realistic as possible, and have a really gritty, rundown look to it (it's abandon).

Basically, I'll probably just use premade walls, ceilings, and floors, and put them together to create rooms and hallways. Although, to do this, I'll need to throw in windows and doors, so it can't just be squares with textures (I'm going to probably use door models, not just textures of doors or windows).

I'll narrow it down to exactly what I need help with, so that way I won't confuse you guys :-)

*Size ratios of certain props (such as a square for a wall) and the textures being put on them. Basically I'm not sure how to know how big a prop should be when putting a texture on it. Lets say I make a specific hallway texture that's a certain height, so I'll need to know how big to make the square (being one of the walls) so the texture doesn't stretch, loop over, etc.

*How do I save or export the whole thing as one single figure? When I use it, I don't want to see all the figures and props made to create it... I just want it to be one single figure.

*Tips on realism? I want to use some pretty high res textures and bump maps, though not too big so as to crash my PC :-(

That's it for now, but any more tips would be greatly appreciated. Also, if anyone knows any place where I can download already existing ceilings, walls, etc. so I can just piece them together and save me time, that'd be phenominal! I'm also looking for more realistic textures, such as tiled floors, etc.

I've seen some hospital interiors, and though they're good, they're still pretty fake looking. Since my animations so far have been pretty good looking (using Stonemason's great sets, and DAZ's people), I want the hospital to fit right in with the realism.

Sorry for being a newb, but I'm trying to learn! Thanks for any help!