@Jay Bamrah just to close the loop on the top thread, the EcuTek packages are as follows:
ECU License: Usually around £250, this is to allow the ECU to take an EcuTek ROM. The ECU only needs this the 1st time it's flashed, so there may be 2nd hand cars that have this already.
Programming Kit (or the BT EVI Kit) with Dongle: The Dongle is the part that allows use of the ProECU software on your PC/Laptop. This is used to flash and log files to the ECU. You do not need this if you're getting tuned by someone else. Needed if you're remote mapping or logging. Can be used to make basic maps for your car and can be used to flash OTS maps if you want. The cable or BT EVI is just the device to connect laptop to the OBD port.
RaceROM Upgrade: This is basically a Tuner License lite. It's applied to the dongle and is there to give you greater access to maps, including the custom and RaceROM maps, for self tuning. So this allows you to create better maps, but makes zero difference if you are flashng someone else's maps.
https://www.ecutek.com/Products/Retail/ProECU-Programming-Kit/Features/ProECU-BRZ