scenery question

What I have seen here on the forum were 'pop-ups', or lift out access sections. Some folks have used the Top Side Creeper type devices like the one from Micro Mark. I think the lift our sections are by far what I have seen the most of here. 

Some folks also make a scene or area of the layout on a piece of plywood or foam or something and place it on the layout after it has been completed. I don't know how well this would work with a multi-level layout though? May not be such a good idea for that??

Just a couple of thoughts... 

I feel for you. When building my large mountain, much of which would have been out of reach, I did it in phases leaving parts open under so I could lay down temporary platforms where I could sit/kneel to be able to reach the parts out of reach when the job was finished. I then went back and closed off these access areas after the upper reaches were finished with ground cover. If you use foam, it will be light enough to build off platform and move into position. If you go with plaster and some substrate, in my case, cardboard strips, it will get heavy pretty quickly. I wouldn't want to attempt to lift my mountain into position.

I use the topside creeper and it works great. I've also made a couple scenes on the bench and dropped them in. Everything I've built I have done with foam, lightweight, no messy water, plenty of time because you are not rushed with it drying.

Pop-up hatches don't have to be flat. Here is one I made in the form of a 3-d module that both covers a hatchway and also provides access to the track under a tunnel. It can be removed or replaced in less than a minute.

I have both pop-outs and a Topside Creeper. Frankly, without the Creeper, there are areas that I just couldn't get to. They not inexpensive (search around) but for many areas, they're invaluable. 

Jerrman

For dem' hard to reach places, hard to beat a topside!  Russ