In our new construction, it is roof first, some one should show the roofers where all new or different vent stack or anything going thru the roof will be so they can install the boots. then install windows order the gutters to come before you do siding so you might be able to do siding in the rain. Then you do the house wrap. The plumbers and electricians and HVAC have all installed what they need to be installed out side so you can seal all the entry points. They may come and just do stub outs even if they are not doing the rest of the work right now. Then you are ready for siding.