Remove as much of the risk for your 'target customers' as possible and make sure your web page sales copy reflects that loudly.
Offer the most compelling guarantee that you possibly can. As long as you have a great product/service the general 'rule' is, "the stronger the guarantee, the less claims on that guarantee".
A good guarantee will have a huge impact on the amount of sales or enquiries that you generate online.
This is one of the most important elements of your sales copy and one of the most important fundamentals for your website. People are still skeptical about buying on websites, and although this attitude is slowly changing, it is important to reassure your buyers as much as possible, and remove any perceived risk.
Make a 'song and dance' about your guarantee, as it is a key tool in gaining the trust of your buyers. Remember, the first order is always the hardest!
Take a risk with your guarantee– make it compelling. Remember, people are generally honest! It is more likely that the extra sales and profits your compelling guarantee generates will hugely outweigh any increases in claims you may have on your guarantee (such as an increase in 'returns' from customers). Besides, if it doesn't work - you can always change it.