Ideally here is what I would want to have in a kit, in no particular order.
1) 10V Voltage Standard (Geller Labs)
2) Metal shield for Voltage Standard
3) Power supply for Voltage Standard
4) GPIB to USB controller. Smallest and lightest available (initially this would only be driving one instrument at a time).
5) Temperature/Humidity sensor (BME 280) and cabling. We may also consider two sensors (one inside voltage standard shield, another next to DMM being evaluated).
6) Raspberry Pi with software that already supports: GPIB, Temperature Sensor, and wide and hopefully growing number of DMMs. It will provide HTTP interface, common logging format and whatever else we need, including posting files to public server.
7) Low thermal leads leads for voltage standard (possibly just pure copper wire with Teflon insulation). It must be easy to connect to both voltage standard and banana plugs, since many participants do not have binding posts). Maybe use Pomona 5405 and pure copper crocodile clips. Some input from more experienced members is needed here.
8 ) 10k Ohms resistor. 10K is probably the best value. Anything much higher than that is harder to measure precisely. Ideally this resistor should be small and light (easier and safer to ship), have 4 wire low thermal connection and wiring, have fairly low thermal coefficient because many members cannot control temperature and be time stable. Maybe this could be a custom wire wound or z-foil resistor in small metal case with copper wires permanently attached. Help of experienced members is needed here too.
9) Low thermal short, to measure zero offset for volts and resistance, and also noise. Fluke 884X, plus possibly draft guard for it.
10) Padded case, like cheap Pelican copy from harbor freight:
https://www.harborfreight.com/watertight-protective-case-small-63518.html. Alternatively we can take a look at custom padding for Small or Medium flat rate box from USPS.
11) If the Voltage Standard is capable of driving 1mA without loss of precision and resistance standard is not compromised by continuous 1mA current, we can also have 1mA current standard, making sure required cabling is included.
Essentially everything but your meter will be included in the package, guaranteeing the highest consistency possible.
Items that we do not yet have are fairly inexpensive and I will be happy to contribute to the cause.
Since everything is already prepared the time per hop will also be minimal. What do you guys think?