A tripwire is a marketing technique where you get interested leads to your website by offering them an extremely low priced item and then you upsell them from there.
We suggest that you don't sell anything under $200 because of several reasons -
1) Anything below $200 attracts people looking for a deal and they end up having a lot of questions and sending back items which means that you have to spend more time dealing with customer service and returns. Just because they purchase the low priced item doesn't necessarily mean that they are going to also purchase the more expensive item.
2) Anything under $200 means that you have to sell a large number of those items to meet your monthly goal. If you sell items $200 or more you only have to sell a small amount to meet your goal. Also, you don’t want to sell anything over about $1000 because then you attract pretty wealthy people and they tend to ask a lot of questions and send items back a lot.
We do suggest trying to do add-ons/ upsells while your customers are checking out to increase your profits. Additionally, you can market your offers with low cost (to you) freebees... something like "Buy [X] item NOW and get [X] for free!". That sweetens the pot for your customers creating brand loyalty and doesn't cost you a lot.