Trailers are awesome no matter what because you are not using a car. Personally I don't have a trailer, but I built a cargo bike to carry my kids and any cargo I need. So far 250 pounds is the most cargo I have carried.
I worked on a Budnitz #3 last week at work. It's a beautiful bike. I like your much less expensive replica, especially the polished finish and the sexy stem. Only thing cooler about the actual Budnitz is the titanium. Sweet work!
The Girvin fork is a 1" threadless steertube requiring a 1" threadless headset. The 1" headset will only fit into your frame with a 1 1/8" to 1"headset reducer made by Wheels Manufacturing. Basically it is an aluminum reducer that presses into your frame and the 1" headset fits into that. It is...