the complex environment in which SMBHs are growing. The paper is organized as follows: in Section \[sec:sample\] we present the megamaser sample, and the X-ray analyses with a brief explanation of modeling and some notes on individual sources. Section \[sec:results\] presents results we obtained combining the spectral and maser disk parameters, with a toy model. A discussion of the toy model is given in Section \[sec:discussion\]. We give a summary in Section \[sec:conclusions\].

Data and Spectral Analysis {#sec:sample}
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The Sample
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To build up a sample of disk megamaser sources with high quality maser maps, precise black hole mass estimates and hard X-ray spectral coverage, we cross-correlated a list of VLBI-mapped water megamasers from the Megamaser Cosmology Project[^1] (MCP, see [@2012IAUS..287..301H]) with *NuSTAR* observations and well known disk maser sources studied in the literature. We found 11 objects. We then enlarged the sample adding three more sources with VLBI radio maps available, but lacking *NuSTAR* data (refer to [@2013MNRAS.436.3388C] for X-ray and maser disk properties of these). The total sample is then composed of 14 sources, which are all the disk water megamasers known today with both precise VLBI maps and hard X-ray spectra. Their main properties are listed 