I worked for two years without compensation, as the chairman of a garage cooperative of my village. 

We take turns working in this capacity.
On Monday, April 8, 2013 I retired from public transport and I turned in my last report.
Now I'll turn my position over to the new chairman of the garage cooperative.
This was a collective decision. (-or- unanimous?)

Sorry I wasn't very clear on your meaning. Perhaps you should also write it in Russian so that I can see what you mean.

We do it one by one

I live in the village.
I worked for two years without charge chairman garage cooperative.
We do it one by one.
On Monday, 8th April 2013 I went to the pension fund by public transport.
I passed the last report.
Now I give the garage cooperative new chairman.
This decision was taken collectively