I did take that into consideration..
So living in the same city - midway - would cost around 8000 Eur (add stress to that) and the housing cost will be taken care of by my company..
Living in different cities.. 800 Eur (housing) + 1000 Eur (for commute durng the weekends)..
But I think I missed out one vital information from my original mail.. I have a 2 year old son who will be joining me with my wife.. so looking at daycare options too.. I know its just become a way lot complicated now..
I am sorry to say that it is unlikely to find day care that will be available for at least 12 hours per day. Not to mention that it would also be very pricey. I think there are a few state Kindergartens in Berlin that offer long opening hours and a few private ones as well. But 12 hours would pretty much take every single minute a 'Spätkindergarten' (Kindergarten that is open late aka after 6 pm) and expect trouble if you are late, which is completely in the realm of possibility when commuting nearly 200 km.
Actually, you would probably need 13 or 14 hours since you need to drop off your child (it does take longer than five minutes, believe you me!) then get to the train station, commute, work, commute, get back to the day care. I think it will be pretty much impossible, not to mention cruel toward your son.
A 'Tagesmutter' (a person who takes care of several children during the day at her own house) is more flexible than a Kindergarten (opening hours vary from facility to facility and also Bundesland, town...)
Then there is the fact that there is no legal right to a day care place for a child under the age of three, so finding a place no matter the opening hours might be a challenge in the first place. The west of Germany is notoriously bad at providing day care places for children under three.
This is of course your personal decision but there is absolutely no way that I would subject my children to something like this. You will not see your child awake during the week at all.
Let´s say you miraculously find a day care that is open all hours of the day - what happens if your child gets ill?
Children who start day care get ill all the time because their immune system has to adjust to the stress and the exposure to so many people. How will you quickly get there to pick him up when you are so far away?
You have quite the challenge before you - relocating to a totally different country, working in two different cities and doing all that with a small child.
Do you live in a joint family system right now? If yes, the difference will be staggering.
Whatever you decide, it will not be easy. I feel for your wife. Being a single parent during the week and working full time will be quite the feat.
You could of course commute, get a bigger apartment and get an au pair girl (or rather two because they are not allowed to work 12 hours per day) but the au pair girl(s) will need their own bedroom(s).
Good luck with all that, you have some hard decisions to make.