I think most people will tell you this is not the best way to proceed. First of all FM can easily handle all the data without performance issues.
Depending on your DB structure, easiest starring point may be to put a radio button on the layout with 2 values-'For Sale' & 'Sold'. Then you could use persistent sort and script triggers to show 'For Sale' or 'Sold' records. This makes it easier for reports, and easier to mange/use the DB
But if you insist to go the way you described, look at a script using export Records
Thanks for the advice, I didn't really know the best way to handle this, which is the reason i posed it on the forum. I will attempt what you suggested and see if I can manage with my limited fm knowledge!
To expand on Steve's advice, with his set up, you can perform find for sold or unsold records to pull up lists of records either for the items sold or those that remain unsold very easily--either by a script or by manually performing a find.
But I'd use Import Records to move blocks of records from one table to another in FileMaker. Export records exports to a text or other type file and then you have to import from the text file with Import Records so the straight import is simpler and faster.