When you mention 'profitable models', is this a side venture?
Online profit depends on popularity it seems to me and profitability equates to 'turn over' which suggests an immediate marketing strat of low price, placement and support.
I personally have no experience anywhere except for ability but my ttutor has and one thing he hammers home is 'Comfort Zones', make em happy first, then happy again and finally, make em really happy.
If you like, Id like to extend my experience base and work on something tiny for you to determine mutual grounds for your project seeing that time is flexible.