Have a peek at this great idea for the tent from Dunechaser. Look carefully and you will find - ramps!
I also like the shell holes/bullet holes in the wall. And the foilage. And the half-track. And the Dodge ambulance. Lots of close ups and angles on Flickr.
He also has the Brick LEGO scale model calculator - that could help a few people. I will put it in my permanent links at the top of the blog for a reference for everyone. If you use Excel then it can be downloaded from the Microsoft Office official website at:
http://office.microsoft.com/en-us/templates/brick-scale-model-calculator-TC101995057.aspx
Check out Dunechaser's full photostream at:
http://www.flickr.com/photos/dunechaser/4851764226/