I think the issue is with Dragonborn but since it affects Hearthfire i decided to post it here.

After installing Dragonborn, Hearthifre seems kind of bugged. Never had this problem before. When i start a new character or load an old one i still get/have the letter from the jarl of Falkreath, but when i talk to him the options to buy the plot are missing, the same happens in Morthal and Dawnstar. The map marker for the plots are also missing, but the clay and stone deposits are still there. I've cleared the cache and reinstalled both HF and DB but the the conversation options are still missing.

Has anybody encountered a similar bug and has any solutions or ideas how to fix this?

Mine runs completely fine.. Although this doesn't help you personally, it could mean that it's your console causing the problem (If that can even affect it..? Idk much about the console and what it can actually affect, in terms of bugs). :/