Do i take out and replace old flashings hood etc.if im going over the origanal roof and going over with second roof on top of old roof
Absolutely replace flashings. One of the many reasons we do not do overlays is if you do them correctly the extra prep work has you halfway to the cost of the tear off.
I would take them out and then reinstall them otherwise you’re going to have to cut around them and mastic them which isn’t going to last, just better to take them out fir it in and either reuse them or replace them depending on their condition
Penetrations with surrounding roofing will need to come completely up and replaced.
All roofing touching flashing need to be removed.
Replace wall flashings?
Depends on if it was of good quality and able to be cleaned well or not.
Always be prepared to do it
But it is not automatic.
26 g steel can last 60 years plus.