What is the most affordable ship in auec that can haul the 2 seater roc-ds?

Can you elaborate why you like the DS more? Are you with a buddy, or do you switch seats whenever you found a cluster?

Can anyone confirm that it will fit in the Nomad?

There's a whole: Will it fit? Guide here: https://robertsspaceindustries.com/spectrum/community/SC/forum/3/thread/will-it-fit-ship-amp-vehicle-guide-3-17-4

Looks like there's a trick to getting it to fit in the nomad.

You could probably rent it cheap for a day just to verify. Looks like the ship sells for a little under 1mil aUEC at Lorville: https://starcitizen.tools/Nomad#Universe_availability

Otherwise you could fit it in the Freelancer Max which goes for a little over 2mil aUEC.

Other ships it fits in: Valkyrie, Corsair, Constellation (Taurus and Andromeda), MSR, HH, Hercules, 600i, 890J.

Constellation is the smallest tone that can carry, since DS is the size of the ursa

Apparently it has the same footprint as the URSA, so anything that can fit the URSA can fit the ROC-DS. According to https://scdata.io/ship-cost-uec-dollar-ratio/ the cheapest AUEC option is the Constellation Andromeda.