Just one more thing in general.
Most suppliers have little knowledge about the POS equipment they sell which makes it hard for people new to this area.
Unfortunately, not all equipment brands and models are available in all countries. This is where the power of the forum can help. If you need help selecting equipment, ask here and we will all try to help to find a local supplier.
Rule #1 - Cheap is not always good.
I started with equipment from de-installed supermarkets that a friend gave me, and equipment from some of our service contracts. So at the least I can prove that you do not need all the same brand of equipment, but check on compatibilities and research the equipment as much as you can that is available to you in your country. And don't be afraid to use eBay for research and purchasing equipment.