I think you have to main consumer groups, those that value credibility over price and those that are price buyers specifically, where credibility of a seller plays a much lessor role to the value of the product.
So how do you counter both?
My advice is to produce a professional image. Of course the more feedback you have the more credibility you will have among that core group of consumers, but if you don't have the feedback, then you should at least present the best possible image. Within that image, you take the opportunity to then introduce yourself (your business self) as a new company, venture or whatever and you use that as a plus, not a negative.
So welcome to (such), we're (about us) and as a special offer to our new customers (insert special offer here)
So you've introduced your business, you've told customers all about your business, your products and your service and now the final hit is the special offer. The intro side caters to the credibility factor, the special offer caters to the price factor, so make the special offer good.
Even if you list 6 products at cost, that is what they cost you all up, all costs taken into consideration. Yes, you're not making money, but you're building a customer base and that builds long term credibility.
A really important thing to remember about any business is that it's a marathon, not a sprint. You can't be successful in business over the first 4 weeks, doesn't matter how many sales you get. If you're not there for the 5th week and on, then it wasn't a success. So it doesn't matter how slowly you have to crawl to get started, getting started is the most important part and then you have something to start building on.
Regarding reviews, I don't personally put much credibility into any reviews unless through something like the BBB. If I was going to sell a product I had never personally seen, I would buy one for myself to test it before ever trying to sell it to someone else, unless it was a well respected brand in the market place.