E-tune-up from gray merchants

According to the observations, there is a rather noticeable group of buyers, formed even before the stagnation of the economy, who are dissatisfied with the quality of work of our online stores (Belarus; a typical and store here is something like that ) and agree on a difference of 10-15% prices subject to "white" goods, normal warranty and well-functioning delivery system.
Suppose someone (and even if I - why not) creates an i-shop that meets these characteristics. But how, taking into account that the absolute majority of users come from the search and do the viewing of a product / store no more than a second before making an impression - how, by what means, have time to convey to them the difference between your store and the "others"?
The first moves, in principle, have already been found: the delivery time is indicated for each item (1 day, 2 days, 3-5 days). This demonstrates that the store at least has real information about its warehouse logistics. The dialogue with the seller-consultant, initiated by the seller, should also work well. But these are just a couple of ideas ... how else can you immediately show the visitor that this store is working for him? Of particular interest are thoughts on how to emphasize the “legality” of the product being offered, so that it can be understood at a glance.