After the Raising of Night-5e
Downtime activities can be found on page 187 of the PHB and additional options on page 128 of the DMG. I have also decided to add some more found on https://worldbuilderblog.me/.
Brief summary to follow.
Crafting : If you are proficient with the tools, you can craft non-magical items, including adventuring gear, and works of art. Depending on what you are making, you may need special equipment, ingredients or locations. Multiple characters may work on the same project to speed up the crafting time. For each day of downtime you spend crafting, you can craft one or more items worth a total of 5 gold. You’ll need to expend raw materials worth half the total market value. So basically you’ll be spending 2.5 gold to make a 5 gold item.
Practicing a Profession : You can work between adventures which basically covers your lifestyle expenses. Depending on your profession, you may be able to turn a small profit, very small. When Truman trains the Isrick Cairn’s militia, he is practicing his profession.
Recuperating : 3 days of recuperation allows you to make a DC 15 Con save. Succeed and you can either end one effect that prevents you from regaining hit points or gain advantage on saving throws versus a disease or poison currently affecting you.
Researching : Self-explanatory— adds 1 gp at least to your lifestyle expenses. Depending on what is being researched or sought after, this may involve other costs or checks. For example, Durgen researched how to craft magical ammunition when he had downtime…
Training : Learn a new language or gain proficiency with new set of tools. Need to train for 250 days and spend 1 gp per day.
Build a Stronghold : Once you have secured a deed or charter of ownership, you can begin to construct. See the DMG :)
Carousing : Drinking, gambling, wenching…ah, the good times we had.
Crafting a Magic Item : Once you know how to craft the item, and have acquired the formula to enchant it (from research or as a reward), spellcasters can craft items. See the table in the DMG.
Gaining Renown : If you belong to an organization, guild or militia, you can attempt to improve your reputation and standing within that organization. Various benefits could accrue, such as promotions. I have sort of hand-waved this one as Truman and Grumelrick did various things that earned their promotions…
Performing Sacred Rites : Spend 10 × 8 hour days in prayer, ritual and meditation to gain Inspiration for 2d6 days.
Running a Business : So you have invested some of your loot into a tavern or other business. There is a small table in the DMG to cover what happens.
Sowing Rumors : You spend time and 1 gp per day to try to influence public opinion about a person or organization.
Selling Magic Items : To sell an item, you make a DC 20 Intelligence (Investigation) check to find a buyer. Fail means no buyer is found for 10 days. Success means you roll on the chart on page 130 in the DMG. You need to be in a community large enough to support the trade in such items.
The following are not-official and are taken from James Introcaso at https://worldbuilderblog.files.wordpress.com/2015/06/downtime-activities.pdf
Build An Organization : A character can spend downtime between adventures creating and building the membership of an organization. The organization could be a guild of thieves or mercenaries, a church, a collective of magic users, a group of activists, or anything group of people with a common cause. Work with the player to come up with a mission statement for the organization. To start the organization, the character must have a place for members to meet and spend at least thirty days and 100 gp recruiting new members. This time need not be spent consecutively. At the end of the thirty days the organization is established and the character has recruited ten members to the organization.
Once the organization is established, the PC can spend downtime assigning jobs to recruits to gain money for the organization. Every day of downtime the PC dedicates to assigning work (such as collecting donations, dues, contract fees, etc.) the PC earns 1 gp per recruit in the organization. The rest of the funds collected go to upkeep the organization.
Buy A Magic Item
In most worlds few people have magic items and even fewer are willing to sell them, but there are those out there who occasionally come across an item for which they have no use. A character looking for a magic item can spend downtime searching for a buyer. This downtime activity can only be performed in an area where the character can find lots of other adventurers or wealthy folk like a city or guild hall. Legendary magic items and artifacts cannot be bought during downtime, since these items are so rare and priceless. The character must make a DC 20 Intelligence (Investigation) check to find a seller of an item with a generic description, such as “a magic sword.” If a specific magic item, such as “a sword of wounding,” or an item with a specific ability, such as “a staff which lets the wielder cast fireball,” is desired, the character must make a DC 25 Intelligence (Investigation) check to find a seller for the item. On a failed check, no seller of the item is found after a search which lasts 10 days. On a successful check, a seller of the item is found after a number of days based on the item’s rarity as shown in the Purchasable Magic Items table. Because of the research and investigation required, a
character can only look for one magic item at a time. If the PC finds an item for sale, the player rolls on the Buying a Magic Item table, applying a modifier based on the item’s rarity, as shown in the Purchasable Magic Items table. The PC also makes a Charisma (Persuasion) check and adds that check’s total to the result. The subsequent total determines the seller’s final sale price of the item.
Create Cover Identity
It doesn’t hurt to have an identity to fall back on. At anytime an angry cult, government, former lover, or mob of monsters could be trying to track a character down. A PC can spend time establishing a new identity for when things go bad by forging documents, creating a disguise, and presenting the
public with an alter ego. Creating a false identity requires a character to stay in a specific area for a time to help spread the word of this new
identity. The more populated an area is, the easier it is for that PC to create a new identity since there is less of a chance the PC will recognized. Likewise the more famous a PC is the more difficult it becomes to create or maintain a false identity, as the PC might be recognizable to even those who have yet
to meet the character. For every day spent creating a cover identity the PC must spend 1d6 gp.