Nah, nah, no please don't. I wrote a WORKING ECONOMY. D&D 5e (and every other edition) had NONE as per RAW.
First it would be 200 Silver in my case for the starting.
I did a working economy for my greyhawk campaign (and every other) but I go nothing like RAW.
I try to give you some examples from my in game pricelist on how to eventually do that:
I my games it is 1g is 20s is 240c to reflect some reality.
So in my campaign a stiletto is 10s a two handed sword is 100s.
A buffed armor (AC12) is 20s a breastplate is 100s a full plate is 800s and needs to be bodyfitted
A mage scroll is (Spell-level)^2 x 100s, so 100s for a level 1 scroll and 8100s for a level 9 scroll.
Those scrolls can be used for oneshot or copying into spellbook, I do not bother about ink and stuff it is minor expense.
You see now the fighter comes with 200s, so e.g. he can buy a two handed sword and a breastplate, and the wizard gets 2 level 1 scrolls for that dosh.
Of course you got to steer the treasure from the beginning, normally every humanoid drops a few silver e.g 1d6 for an orc.
I hope that clarifies it a bit what I mean
I'm not sure what most of that had to do with anything. And unless Helldritch is using your economy instead of the rules in the book, then my numbers are more accurate to what they are doing.
I think some people here are confusing paying for additional spells and paying for copying.
Bob the wizard is now third level. He has the chance to be in town.
He leveled in the field so now he wants to copy his new spells into his spellbook.
2 first level must be copied. It cost him 100 gold to get them down.
2 second level must be copied. Both are of his school so again 100 gold to get them down.
He wants to add a third spell second level spell. He goes to the local wizard that thought him magic and wants to add the blur spell to his spell book. Being a former apprentice, the wizard charge him 100 gold for the right of copying the spell. It costs an other 100 gold in inks.
Understood that just fine
And it goes both ways.
snip
Meanwhile, Tarkud the Fighter, pays for the repairs to his armor, shield and weapons (about 10% of their value). He buys new magical arrows and goes to the alchemist and apothecary to buy potions. He knows that Bob will make a few potions of fire resistance but he does not expect that Bob will have time to make a lot of them. Maybe two or three. So better check with the local alchemist. Healing potions are costly too but hey... At least they turned up a good profit on this adventure. The same goes with Albrecht the priest, and all the other characters. Everyone pays for something.
Okay, pause button.
So, you never mentioned that the Fighter is paying for repairs before, this does change things.
10% of the value. It looks like your group is still around level 3, so he likely has chainmail still (well, he shouldn't but we'll talk about that in a second)
So, making some number assumptions. Chainmail costs 7.5, shield costs 1, longsword 1.5, and longbow 5
Tarkud the Fighter has spent.... 15 gold on up keeping his equipment.
Bob the Wizard spent 200 just in copying his "free" spells.
In fact, Tarkud could have platemail which costs 150 to upkeep, giving a total of 157.5 gold and still be less.
Which is why he can buy magical arrows (new gear that isn't part of the upkeep) and potions. Which, while Bob can make if I assume you are going with the crafting rules, Bob is still spending money on.
Which, really starts getting ridiculous if we assume everyone has the same amount of gold.
Bob spent 400 gold between copying and buying one spell, assuming he isn't broke and can still afford to buy materials for potionmaking (which he will give to the party) he had to have somewhere between 500 and 600 gold, leaving him about 100 to spend on whatever he would like.
Now, my group tends to divide treasure evenly. Which means if Bob has 600 gold, then so does Tarduk. Who, assuming chainmail, has 585 gold to spend on whatever he would like. Which would of course be better armor, so he wouldn't pay for the repairs to his chain. Splint is 200, so he still has around 390 gold left for those magical arrows (buffing) and those potions (extras)
So, the wizard got a single new spell, and copied their class level up gains over, while Tarduk upgraded his equipment, bought magical items and potions to buff and heal, and is expecting more potions from Bob who is spending even more money on making Tardek better.
And, if every member of the party got at least 600 gold, that is 2,400 gold at 3rd level, and they'd likely invest in some plate.
And, let us jump ahead to the future of level 9. Where Bob is potentially spending 500 gp just to copy their spells they earned for free, and unless Tarduk is having to pay to maintain 5,000 gold worth of gear he is still paying pennies compared to Bob.
He was in adventure. He rose from 1st to 2nd then from 2nd to 3rd. 4 spells total.
Edit: For clarification, you might not get your free spells in your book immediately, but you do have them prepared as flash of insight. This also means that you might have to unprepare some spells to make room for your insights but it is generaly a minor inconvenience.
Um, an inconvenience?
Wizard's can't prepare a spell they don't have in their book, right? Per RAW, that would mean that unless they prepare these "insight" spells immediately and never un-prepare them they would lose them forever.
And since we are talking levels 2 and 3, where they only have likely 6 to 7 spells for prep, they are locking in over half their spells. That is more than a minor inconvenience.