Alumawood & Beamlyft 

Your putting holes in your roof either way, skylift is stronger due to being installed on the double top plate of that outside wall.

Skylift are $200.00 per bracket for the smallest one.....

I wouldn’t do Skylift. The opening is just too much for rain water.

You could just use angle iron or standard home depot attachments for flat

Anything is possible. You need to make sure your connection with what you are building on is good, like appropriate rafters and load bearing walls. There is engineering

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