Why can't I upgrade the inside of my house?

I have a house in Whiterun and I managed to get a few things for it from the Jarl's assistant guy in Dragonsreach. Recently, I've 'acquired' quite a bit of coin and would like to finish upgrading. Unfortunately, when I go visit him now, there is no option to decorate like there was before.

Now, was I supposed to keep lugging around that stupid interior design book in order for this to be a regular dialogue choice? If so, I totally sold that about twenty levels ago and have no idea where to even start looking for it. Is there any other way to upgrade my house other than the Jarl's assistant? If not, is there a console command for adding that dumb book back into my inventory? Would that even fix the issue at this point?

Solution 1:

I've found that the Steward can be a bit touchy when it comes to offering the upgrades - the simplest solution is to either wait 24 hours and hope that he moves (and remembers his duties) or simply come back later.

Solution 2:

Jesse Cox of OMFGcata noticed this problem: it's not exactly bugged, but there are only certain conditions under which NPCs will sell you things: time of day, whether they're in a scripted piece of dialogue, etc.

The issue is that the Stewart won't sell anything to you until he's in the appropriate area, which is inside Dragonreach. If he's having a grand old time outside, you have to wait until he meanders back inside. Once there, he'll sell you all the decorations you can buy.