What to upgrade on my site? $500 to invest

Congrats on your site - looks good. So personally I wouldn`t change the design.

As a 2 min job, lose any traffic leaks on your pages (just glanced at your main page and see your counter button at the footer).

Buying traffic is certainly an option but just be aware of what you are buying to ensure that it is highly targeted to your niche (ensure targeted text descriptions/banners are used with traffic that has a decent geo so U.S, UK, Canada in the main).

Designs is pretty good....but at a short glance...i can't figure out if it is a free site or a paysite.

If those are your choices I would go for item 4 first, followed by item 1. The only problem with item 4 is actually finding someone who DOES know about this industry and isn't just bullshitting - chances are if they DO know what they're doing then they will be too busy making their own money to sit there teaching you. But if you CAN find someone then you can never have enough knowledge in this business. I think you could redesign your site a lot better but I doubt this would have a huge impact on sales - similarly buying traffic from a broker will just increase your traffic with crap that doesn't purchase anything and buying hardlinks will help with your SEO but needs some knowledge to buy and use the correct hardlinks - again coming back to the fact that knowledge about what you're doing is the key thing.

you're no fun!

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if you buy traffic buy chokertraffic (chokertraffic.com). I recommend making some onsite SEO changes and buying some ChokerTraffic at the same time

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