IF you are looking for only a 4x4 field for doing monograms only - and small ones at that - not for bags and purses - you can get away with a cheap Brother you can pick up at Walmart. I will be honest when I tell you that you probably will not be happy with it. I bout suggest getting the Brother 780. It's about $800 or so and it has a 5x7 field.
See if you can find a dealership that will also throw in something like monogramming software or something ;)