While letterpress stationery is typically on the more expensive side, there are still many variables that go into determining the cost of letterpress printed items. Some of the factors that contribute to that cost are the type and quality of the paper, how may ink color are used, and what else goes into the design such as additional layers of paper, ribbons or other embellishments.
Most letterpress printers like to use 100% cotton paper, which gives it a soft, toothy feel and a deep impression. Also, many cotton papers come in a variety of thickneses, including some so thick they fell like cardboard. Cotton papers are on the more expensive side and obviously, the thinker the paper, the more expensive it is. Other papers can be used that are recycled or a combination of recycled and cotton. These tend to be less expensive, but also less thick and not as soft. On the really high end, there are handmade papers, which are all cotton or a combination of cotton and recycled materials. Because the process to make these papers are completely by hand, they are usually the most expensive, but also can be the most beautiful because they can include things like flower petals, recycled bits of catalogs and even scents.
Many printing presses are manually operated, like my Vandercook, where it is hand cranked and one piece of paper is fed through the machine at a time. A one color print job is going to be less expensive than a two color print job, usually by a significant amount. A two color print job is twice the labor because it requires twice the set up, feeding the paper through and clean up.
Many of my designs use several layers of paper, decorative papers and ribbons. These can take letterpress to a completely different look, but also a different price level.