Downtime Ideas

What a character does in their downtime or might do when they next get some

Sign your group up to every quest available in the area
Sell useful information you have picked up on your adventures, to whoever wants it
Follow the shadiest member of the party everywhere
Research cursed items no-one will ever want
Interview locals to use as hirelings for the next adventure
Find traps for your home base and convince others to buy it with you
Join in with local patrols
Insist on group training sessions to prepare for dangerous situations
Find a mine and convince others to buy it with you
Develop contacts and allies with the local criminal underground