I started with a Brother 8500D it did up to 5x7.
I think the bigger the better and now have 2 machines. I purchased a Duetta almost 2 years ago and I love it. It does up to 6x10. It is a great machine and very user friendly. Then last year I got a very good price on a Pfaff CV that has an even bigger embroidery area. I love that machine too!
I would buy the best machine that you can grow into!
K