Measure the consumption of a LP application

Hi, so Im currently making an IoT application with some RAKs wisblock modules.

And now Im in the process of choosing a battery with enough capacity to last at least 2years without dying.
So I need to measure the consumption of the application, the problem is that I dont know how to do it properly, I have been looking at some power profiler like the PPK 2 from nordic but its a little expensive for me. Is there any cheaper way to measure the consumption of the application? Or even make a diy power profiler?

Thanks in advance!

You can try to use a multi meter which can read DC current in the micro ampere range.
But you will never get an average consumption, you can see only the momentary consumption. So it will not be very helpful.

Another option would be to use a second WisBlock and the RAK16000 DC current sensor
But that gives you only a resolution of 100uA and you need still to write some code to calculate the average consumption.

I am using the PPK2, and it was worth the investment.