  We present a CO dynamical estimate of the mass of the super-massive black
hole (SMBH) in three nearby early-type galaxies: NGC0612, NGC1574 and NGC4261.
Our analysis is based on Atacama Large Millimeter/submillimeter Array (ALMA)
Cycle 3-6 observations of the $^{12}$CO(2-1) emission line with spatial
resolutions of $14-58$ pc ($0.01"-0.26"$). We detect disc-like CO distributions
on scales from $\lesssim200$ pc (NGC1574 and NGC4261) to $\approx10$ kpc
(NGC0612). In NGC0612 and NGC1574 the bulk of the gas is regularly rotating.
The data also provide evidence for the presence of a massive dark object at the
centre of NGC1574, allowing us to obtain the first measure of its mass, $M_{\rm
BH}=(1.0\pm0.2)\times10^{8}$ M$_{\odot}$ (1$\sigma$ uncertainty). In NGC4261,
the CO kinematics is clearly dominated by the SMBH gravitational influence,
allowing us to determine an accurate black hole mass of $(1.62{\pm
0.04})\times10^{9}$ M$_{\odot}$ ($1\sigma$ uncertainty). This is fully
consistent with a previous CO dynamical estimate obtained using a different
modelling technique. Signs of non-circular gas motions (likely outflow) are
also identified in the inner regions of NGC4261. In NGC0612, we are only able
to obtain a (conservative) upper limit of $M_{\rm BH}\lesssim3.2\times10^{9}$
M$_{\odot}$. This has likely to be ascribed to the presence of a central CO
hole (with a radius much larger than that of the SMBH sphere of influence),
combined with the inability of obtaining a robust prediction for the CO
velocity curve. The three SMBH mass estimates are overall in agreement with
predictions from the $M_{\rm BH}-\sigma_{\star}$ relation.
