The first one is a much smaller helium filled ship. The second is thermal. I've looked into them before, and the thermals ones are far too slow and hard to maneuver. Supposedly, they should be cheap to build, but it sounds like you need real Saran (PVDC) material for the envelope of the gas ships, but, last I checked, it was hard to find the stuff anymore, especially in the large sizes needed. If you used H instead of He, the envelope could be even smaller and you could very cheaply manufacture your own lifting gas. The only problem would be hangar size and the high winds we have here in the middle of the US. Supposedly, the most dangerous part of the Graf Zeppelin's round the world flight wasn't Siberia or the oceans, but the Rockies and Great Plains because of our winds and thunderstorm activity.
“Give a man a fire and he's warm for a day, but set fire to him and he's warm for the rest of his life.”
-Pratchett