Do any spouses have more than 750 gold for trading? I've been looking all over the internet and everyone seems to be talking about the 100 gold per day thing and it's really frustrating Alchemists have 500 gold, general stores have 750 gold, and smithing stores usually have about 1100 to 1200 gold and I want to know if my spouse can have more than 750 gold to trade with
You can invest in your spouse's shop to make them have more (500) gold. Getting the master trader perk will add another 1000 gold to their inventory for a total of 1500 gold.
There are also some shopkeepers that you can marry they may have more gold than a standard 'spouse pawnshop'.
Finally there are many mods that can adjust the amount of gold shopkeepers have, for example, the rich merchants mod.