For the Thieves guild the Heist daily quest needs to be done. If you enter the guild from outside the city in Hew Bane through the sewer grate, the heist board is on the left in a small area before you get to the fence down at the end of the tunnel. Fa'ren-dar will be standing there. You must have thieves guild rank 3 and have completed the guild( storyline) quest, " the long game" to get access to the heist. If you never ran the story line it will take about an hour to run it depending on if you are just blowing through it or if your trying to be sneaky and reading dialogue.


For dark brotherhood you have to do sacrament quests which are very similar to the heists but instead of being transported to an instance to steal something, you are transported to kill someone. You have to complete the Dark brotherhood storyline quest "A lesson in silence" I dont remember how long it takes to get to that point as its been to long since i ran that one( DB storyline is extremely tedious).

You do not need to complete the "bonus" objectives only the main objective in heist or sacraments to get a ticket. For the thieves guild for example i dont try to do it in the time limit and be sneaky. I just kill everything collect what i need to collect and leave. I dont do sacraments really anymore. they are kind of a pain and you cant really blitz them like the heist. You end up with a bounty for sacraments.

You would be best off running thieves guild on two characters( assuming you can) for two tickets. I havent tried it on two characters on the same account but i assume you can do it and get two tickets.