@Nazar, parts came early so @brent113 and I finished the exhaust build tonight.
We built a window mount system that we can remove if we so desire. The board is plywood sealed with polyurethane to reduce the potential for weather damage, in addition we adhered coroplast onto the exterior surface so that the wood was not in direct contact with weather. We then ran high-density foam weatherstrip tape on the edges to help seal it up and prevent wind and water intrusion as we live in Oregon and that means we get rained on a lot 
Board before and after weatherstrip is applied (we built the board so that the left side fits into a groove in the window and does not need the extra seal, as a bonus this also centers it in the window frame):
We used 4" dust collection hose and clamps for all the hose connections, so I designed and printed adpaters for the window port and fan connection:
To prevent bugs from getting in there is a piece of screen in the end of the hose at the window and on the exterior we added a louvered cover (like this one).
Installed:
The inline fan (like this one) has it’s own control that we have on the table top and we have the hose system going under the table and up the back to the window:
Fan pressure pushes the louvers open making it really easy to see the difference the inline fan makes(Left to Right: both fans on, only inline fan, only enclosure fan):
Now to get the laser up and running!
