IF Function in Accounting

Hi everyone,

Description
Currently I am a treasurer at a study association and with that comes keeping track of financial information. To keep this plain and simple, this is what I basically do currently MANUALLY:

1. Journal entries (which are basically entries of any financial transaction)*
2. Posting each transaction (or a sum of transactions) to the financial statements.*

*See file under 'General Journal', 'Balance sheet' and 'Income Statement' tab.

Change
As our business is now growing (which brings more transactions), I do not want to keep doing this routine over and over again, since it is quite time consuming. To be more specific, I am looking for a way to
a) perform the journal entries, b) and then let these transactions automatically affect the corresponding accounts (e.g. Cash or Bike Sales) of the financial statements.

For this reason I am using the IF function. To make it simple, I have created 2 transaction numbers for each account (one for an increase and another for a decrease). You can see an overview of all the transaction numbers of each account under the 'Logarithm tab'. For example, if you look at the very first journal entry (14.02.2017), we sold a bike kit for 5 euros and gained 5 euros cash for it. Instead of adding 5 euros to sales and 5 euros to cash once more, I have tried to link the transaction of the cash component to the transaction number 1001. Which implies an increase under the cash account in the 'Balance Sheet' tab. I used the following function:

=IF('General Journal'!$H$3='Logarithm tab'!D2,'Logarithm tab'!C2+'General Journal'!E3,'Logarithm tab'!C2+0)

It gave the result I wanted, namely an automatic changes of +5 euros under the cash account.

Problem 1
However, the problem I encounter is that it only worked for this specific row number. I do not know how I can adjust the function above so that it includes ALL future transactions that are related to cash. Ofcourse I have to do this seperately for the other accounts as well, but I think it is easier to first have one running smoothly before I head to the others.

What I mean by this problem is that whenever I go to another transaction that affected cash and I write down the transaction number 1001, it does not change the value on the 'Balance sheet' since it specifically only follows that one row.

Problem 2
The second problem I encounter is how I can change this formula to also include decreases in cash. I have tried it with several OR statements but I am just too much of a beginner to do something about it I guess.

Excel File
I have included the excel file and it already has the function under the "Balance sheet" tab under the cash account.

I know this quite long, but I hope someone can guide me with this as I am trying to get better in Excel and make it more efficient.

Kind Regards.

Your Dark Lord of the Sith