Keep your eye on ebay. You can easily get a 2Mbyte one for under $40 on a good day.
2Mbytes Chip and 2Mbytes FAST should be enough for anything you want to do with vanilla A1200. WHDload etc.
The cost of a 4Mbyte PCMCIA card is too much. You'd be better off getting a Trap Door RAM card with 8 Mbytes for the same price, or even an A1230 accelerator.
If you dont have a hard drive, you should get one of those first. Either a real hard drive, or an IDE CF card adapter.
