Albion Online alpha program in September? Fifty bucks. Thirty dollars if you're willing to wait for next year's beta.
Now that your curiosity is sated, let's talk about the trio of founder's packs that Albion Online has just made available to buy. The least expensive tier is the veteran pack at $29.95, which comes with beta access in Q1 2015, in-game currency, and 30 days of premium access. The epic and legendary packs are $49.95 and $99.95 respectively, and include (among other goodies) access to the summer and winter alpha program, special nametags, cosmetic outfits, and even (in the case of the lgendary pack) mounts.
Various questions about the founder's packs have been answered on a separate FAQ page.
[Thanks to Laurence for the tip!]