Buy, Sell, Trade the REM Catalog

In addition to selling covers, I am also interested in buying or trading for covers.  I prefer trading, and will allow full catalog value in trade credit for any name I don't have in my personal collection.  I will allow 50% of catalog for any name I don't have in my current inventory.  And, I'll allow 25% of catalog for any name I already have in inventory with a maximum of 4 covers credit for any city per collector, and only if I have less than 20 already in inventory.  To purchase outright, I will pay half of trade values.  That is, 50%, 25% or 12.5% of catalog value for the above respective categories.