My First Series Playsets have a thick cellophane window on them while many others I have seen do not and never did. What gives?
The First Series Playsets Marx sold individually in the early 1960s (for $.98 cents) did not have a cellophane on their window opening and never did. The playsets in the secondary market nowadays which do have a cellophane window all come from First Series Playsets Store Displays (which had cellophane windows on all the playsets). This is the only way those playsets came with cellophane on their window display boxes. This same rule of thumb also holds true for the First Series TV-Scenes. After the First Series all the playsets and TV-Scenes had cellophane.