One of my players argues that to find the price of a used wand you use the following formula.
X= price of a fully charged wand, Z= How many charges it has left.
Used wand = (X/50)xZ.
Now I can see his logic about the math but this results in him buying several low lvl wands (1st lvl spells) with low charges (3-5-10) for prices like 45gp, 75gp and 150gp. He is now 4th lvl (Cleric 3/Wizard 1) and pretty much has about 20+ wands with all kinds of 1 st lvl spells. I have been DMing for quite some time now and this is the first time a see a caster with so much wands. I am not sure if he is more powerful or not but it seems weird. Are we playing this wrong??