I did this a few years ago but I do not have any pictures.
I had a cape cod style house. Stairs to second floor existed. Only one small window on gable end.
I put two gable (dog house) style dormers on front and a large shed dormer on back. two bedrooms, one on either end, a bath and hall in middle.
I hired out cutting in the dormers, roofing, siding and windows. My reasoning behind this was to minimize the time my house was exposed to the weather. This cost me abut $15K about 10 years ago. I then spent the next year, nights and weekends doing everything else. I probably spend 30K to 40K total. I added probably 100K in value and 700 sq foot of finished space.
Off the top of my head...
What I did myself (in no particular order)
Demo except for cutting holes for dormers
Hardwood floors in hall
Framing interior walls
Doors jambs (I used "slab" doors)
Install larger window in gable end
What I hired out
Insulation (Cheaper to hire out actually)
Carpet install (Didn't have the skills or tools)
Duct fabrication (Didn't have the skills or tools)
Dormer framing (Wanted it done fast)
Siding (Wanted it done fast)
Window installs (Wanted it done fast)
Roofing (Wanted it done fast)
Custom built shower door install (Custom door included installation)
My advice - Know your limits. Hire out what makes sense from a cost, skill, time or safety perspective.
Looking back I might have hired out the drywall. I have since found a company that does a great job for about what it would cost me to do it myself and they would have finished quickly. It took me a couple of months to do drywall myself.