Spellcasters (DMG)

There will come a time when player characters feel in dire need of a particular spell or spells to which no one in their group has access. They may need to raise a fallen comrade, remove an evil enchantment, or provide an additional protection. The natural solution is to find an NPC willing and able to cast the spell. This can create special difficulties for both the players and the DM.
==Finding a Spellcaster==
Locating a capable NPC is the first step. Not all NPCs advertise their abilities; this is especially true in the case of spellcasters. Bragging that one is the great and powerful wizard Wazoo can be bad for one's health. There is always a young hot-shot who will take the claim as a challenge. (Sort of like the Old West, where there was always someone itching to beat the fastest gun...)
For this reason, spellcasters tend to be mysterious or, at least, quiet about their abilities. Churches, temples, and other holy places tend to be the best places to look since clerics have some obligation to proclaim the powers of their deity openly.
==Convincing the NPC to Help==
Assuming the player characters know of a capable spellcaster, there is still the problem of convincing the NPC to cast the desired spell. Often the NPC won't even have the spell ready when the characters need it. After all, it isn't every day a cleric needs to cast a raise dead spell. He will need a day just to rest and memorize the desired spell.
Religious Differences: The faith of the player characters and the ethos of the NPC's religion may pose an even greater problem than spell availability. It is quite possible for a cleric to refuse to cast a spell to aid an "unbeliever," "heathen," or "heretic." Some may agree, but only at the cost of a donation, service, or conversion. A rare few accept any and all without passing any judgment. In general, it is best to seek the services of a like-minded cleric than to go to a stranger.
Money: For some clerical spellcasters and most nonclerical types, spellcasting is more a matter of finances than philosophies. If the characters find a capable spellcaster, they must be prepared to pay (and pay dearly) for his services. For a desperately needed service, the NPC knows he has the player characters over a barrel and will bargain accordingly.
Table 69 gives some idea of the costs for different spells. These costs are not set, by any means, and can be raised (but seldom lowered) for a variety of reasons.
In general, the costs of purchasing a spell are such that it is far better for someone in the party to learn the spell. In general, the mercenary use of NPC spellcasters should be discouraged whenever possible. The player characters are supposed to face challenges on their own!
==NPC Magical Items==
If player characters have the nerve to ask NPCs (not hirelings or henchmen) to use up valuable magical items or charges from these, they are going to get a very cold reaction. Consider how often player characters sell or give away the magic items they find during their adventures. Nonplayer characters will have about the same likelihood of selling (or giving!) powerful magic away. Offering to buy a charge from a staff of healing is just plain insulting. No NPC's reaction is going to be improved by the offer.