I don't find them difficult, just time consuming. The 1st year back in the early '90's we had an accountant do them and then got hauled into Condom tax office to be told they had been done all wrong. The tax inspector then did them for us , it took him about 8 months to get it done!!! and ever since I followed what he did the numbers have changed but where the income from hasn't.
Last year we got a letter asking us to go in and another inspector told us the system had changed and therefore our overseas income had to be ventilated into different boxes on the pink form which he kindly marked for me. He then added the overseas income onto the french micro as well as putting it in the apropriate No8 box on the blue form. When I querried this he said that was the new way. later after reflection I called him and pointed out that micro france was turn over and overseas income was profit, so he decided that it had to be added to profit in france as if we had a reel simplifée. Which I did . we ended up paying tax as our income had increased. I knew he was entering it twice he just couldn't understand that! I'm not saying I'm a tax expert but adding the same figures up twice didn't make any sense to me .
This year I have done it my way which means putting it on the pink form ventilated in the way he showed and putting that amount on the blue form but certainly not adding it onto our french income a 2nd time . One good thing I discovered this year is that I get an allowance for the children now they are in higher education and I also spotted that they will be able to claim an allowance on repaying their student loans when the time comes.
I'm just glad it's done.