I did both quests for the Jarls, but they aren't offering me to become Thane and are not offering me more quests.

did you do all of the townie quests? I know riften can bug out on becoming Thane, haven't seen markarth do it.

With Riften i've been able to fix it bugging out by getting the Jarl switched via the war sidequest, or by trading Riften during the peace meeting with the greybeards. after the Jarl got switched I was able to become thane, but no house carl (is there a house carl for Riften? lol, i never use that house)

After the Skooma bust, the Jarl never offered the opportunity of becoming Thane and I can't even buy a house there. However, when Maven was in charge, I didn't have to do any quests to buy a house.

Maven counts the thieves guild quests as personal quests / helping the townies, I'm pretty sure that's why.

in Markarth the Jarl's boot licker (the old man who gives quests) doesn't have the option to "buy a house", it dissapeared all of a sudden, I remember I did a mini quest when you ask him for more work, after returning the buy a house option was gone, so I wont be able to be thane

Really? Thats intresting and I'll make sure to remember that. However, that Character only completed the main quest and did not start any of the faction quests.

there seems to be a bug that when you switch the jarl, i.e. maven, you dont get a house carl if getting the house afterwards. :S I went n' got the house on two chars after the jarl was switched, one via the imperials, one via the stormcloaks, both cases, no house carl. i usually dont buy the riften house, its kinda tiny...little better then breezehome but out of the way for most things.

Disrupt the Skooma trade is stuck for me. The third time I've been sent to that stupid little cave and it was just about empty. The quest marker disappeared after I killed the dude inside the entrance but even after I cleared out the cave the quest is still unfinished. That svcks.