Got a new foam cutter and started on the base of the structure. First the foam cutter, I called a friend who has great deal of exp using foam cutters (he is also cheap) and ask what I should be looking at. He pointed me to Hot Wire Foam Factory tools. They are not the cheapest, but they hold up and work the best. On his suggestion I picked up a Scroll Table as well.
Both tools came out to about $100. The Scroll Table is very useful. I can now make straight lines cuts. The base of the Cathedral is square, I would never have been able to make a perfect square without it. Both tools are plug in which means they stay hot better and don't have to worry about batteries. The sculpt tool is very nice and have given me a lot more option to use in the future of this project. Now on to the building.
I am using Joint Compound available at hardware store for about $10 for a 3lbs of the stuff. It is premixed plaster of paris that dries in about 8 hours. It gives me a more realistic ground base without being sandy. Part of it I will cover with turf and part will end up as mud.
I have started to add in 'trash' into the places that will be mud and cork rock (an excuses to drink wine while working) to areas there will be turf.
The building is not glued down yet waiting on painting.. so there is it so far.