Wealth by level

So, my group is kinda new to Pathfinder (we've played some others adventures before, but I think this is our first serious one) and we're currently playing Rise of The Rubelords. After me and a friend died, we're creating new characters to reenter the adventure. The party is currently at level 4 and so is our new chars, but my DM finds it ridiculous that a 4th level character starts with 6000gp - even though my previous char had 2 enchanted +1 swords and a cloak of resistance, which costs 4500gp total (and that was just me). How do I explain to him that it is balanced like that and it makes sense for a 4th level char to have that much gold?

edit: grammar