It's a good question.. Unfortunately I don't think that any of the options you list is really all that viable..
Sponsor - not really enough cash...
TGP - why bother.
Hosting - See Above.
College Kids - don't know how to market porn.
So, really it's all about expertise. If you've got a shitload of money, you can hire the expertise, but with 50k you almost have to provide it yourself. The cash is secondary, with someone who knows your shit you don't need the captial so much.
Cheers,
Backov
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