I suppose it is possible by designing 2 boards based on the same board outline/vias template and then make printing for Top/Inner1 from first file and Inner2/Bottom from the second file and make hole/via plating after uniting boards. But honestly I don't think this way is good as it is time-consuming + probability of mistake is very high.
If you are hobbyist - please check Non-Profit 4 layer version for $125.
If you are commercial user and plan to make 4 layer toner-transfer boards to sell them - I would recommend to avoid that and use manufacturing method.
Notice number of plane layers is unlimited and 4 layer board with two signal layers and 2 power planes can be made by Lite license.
Why would you avoid toner-transfer method?
Thanks for the non-profit mention -- I might consider that -- as a start-up, I can use some temporary $$ relief.
-- 05 Jul 2012, 14:54 --
I've done this - kind of anyway. (if I've understood you correctly)
Clearly a 4 surface board is 2 distinct PCB's so the issue is how do you line them up so they can be connected in a reliable manner. When I did this I designed both boards (which had a differernet outline) but designated common points between them. Once made, the boards connected together using matrix pins on one board and header's on the other.
In my schematic I designated a pair of connectors - one connector belonged to one board and the other one, the other board. I designed my schematic basically in two parts - all nets belonged to their own board and were bought together at the connectors. So all I had to do was make sure the connectors lined up and all was good.
I have to say, I never used the tonar transfer method but stuck with Kinston board, light box and amonuim persulphate. Since I moved over to SMT I have pretty much all of my boards made professionally - particularly boards for comercial projects. The idea of trying to do 4 layer boards with vias etc across two boards seems like a recipie for frustration! (but best of luck with it anyway) - Just for interest, I get prototype boards made at pcbcart in China - cheap as you like and quite easy to deal with.
All my boards will be 100% SMD. Is there a costing you can share for the China PCB house?
As far as toner transfer goes, I even saw a technique where one guy was putting copper traces on a glass substrate. Reliability unknown.