You might be able to find a decent machine second hand at the dealers. Since you are doing childrens clothing, you may want to look at the Brother line of machines, particularly the Disney line. Not only do you have the Disney designs, you can use a miriad of other designs also. Personally, I would spend more money and go for a combo machine as you always need a backup machine.

I also have a Singer CE200 that is computer dependent and does a beautiful job embroidering. I just have problems with the tight sewing space and trying to change a needle much less anything else. The software pays for itself because it converts designs in different formats.

I think you may have to spend some quality time with your computer to do searches for machines within your price range that meets your needs. It saves shoe leather, you can print out the fact sheets for the ones you like, and then go and investigate those machines.

Also note that the expense does not stop with the machine, just like any other sewing with machine embroidery thread, stabilizers, hoops, needles, etc.