New header for Bi fold door

Planning on having a 4.5 meter bi fold installed into the front of our brick veneer house.
This will need a new header installed, 2 hyspan lvl 350 x 45 beams I have been told.
There is a large window in this wall so that will come out as will the old front door the brick work cut down and removed the header and new studs installed.
Questions is
Is this a job I could possibly do myself, I have been quoted 4k to do this and this seems quite excessive. I have just about every power tool needed and then some and I have just built our 30 sqr mete front deck and stairs

The materials are only approx 350.

How is the roof supported when fitting the new header, I know you use acro props but were are the placed.

Any advise would be great


Read the full thread at RenovateForum.com...