From the website, it is not yet a product, and does not yet have a price.
Happier Camper has a business renovating and renting out old MFG TTs. This at least gives them some experience with the market, what people want who use trailers this small, expectations that might be different from mainstream RVing.
It also suggests some level of capitalization to get into production, and an existing income stream. This is way ahead of many new age ventures that have an interesting idea with a business plan based on collecting enough deposits to raise the money needed to begin production, and maybe wrangling some money from a publicly funded industrial development program.