I don't understand what you mean by new game? This is all a fresh install of Origin and packs no saved files of any type in Documents. Can't I just copy and paste particular files from an old Tray folder into the current Tray file for my own vacant lots I built a few years ago? If I knew which files those were, it won't take but a minute. Household Binary? BPI file? HHI File? Room File? BluePrint file? TrayItem file? I just want the file for a vacant lot/my own builds.
ETA: there are 779 files in my old tray folder. I don't want to put the whole thing into a new TS4 folder.
@rosemow, do you know which of these files listed pertain to my own vacant houses or community lots I built?
ETA: But thank you @GalacticGal , if I don't get an answer which of these are empty lots/builds I will try it the hard way and delete from inside the game. :/