How much are Astros legacy bricks?

I'm curious about the pricing of Astros legacy bricks. Could you please provide me with some information on how much they typically cost? Are there different pricing tiers based on the location or significance of the brick? Additionally, do the prices fluctuate over time, or are they relatively stable? I'm interested in learning more about the investment potential of Astros legacy bricks and how they may appreciate in value over time.