Hey cashdude,
I used to run several tgps in the past. I can tell you that such a site takes time to grow.
There shouldnt be a problem with webmasters who submit to your tgp. After some time you'll be getting more galleries than you can review. The best way to get them is to signup for a webring (where you share your galleries) or just get your site into one of tgp auto submit programms. If surfers like your site - your traffic will start growing. There will be people that bookmark your site. Good way to get traffic is to trade it with other tgp sites.
If you have enough time to build your galleries your site will be more profitable. You will be sending your traffic to your galleries and your sponsors instead of gallery submitters.
If you will get a lot of gallery posts, more than you can handle you can rent stuff to review them. Usually tgp owners dont pay their employees, but allow them to post their galleries at the top positions. Tgp owners and people that review galleries are happy.
How much you will make on your TGP depends....on you.
You can try different combinations of sponsors for example.
If you get more traffic - you make more money. If you get good quality traffic - you make more money...etc...
I wish you luck on your TGP site ;-)
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