¹²CO moment-zero maps of the 17 sources that were detected at low S/N, referred to as the low S/N sample in this work. Cyan contours show significant (S∕N ≥ 3) ¹²CO emission. The top six disks have resolved continuum emission and their R_{mm, obs} is shown by the yellow ellipse. For these sources, Keplerian masking was applied to the ¹²CO J = 2− 1 emission (see Appendix A). The middle eight disks (Sz 66 to J16095628) have unresolved continuum emission. The dashed yellow circle shows the size of the beam (0.′′ 25) as an upper limit to the dust disk size. Similarly, the dashed green circle shows four times the beamsize. For J16011549 the continuum is resolved and R_dust was calculated from 90% of the total flux. The continuum emission of J16070384 and J16090141 is resolved but irregular in shape. Here, we show the 3σ contours of the continuum in green.