damn 1k char limit

The construction itself could be done through interaction points on the house in construction which then bring up the crafting interface. Construction would have difficulty and progess could even fail.

A system as this would also allow for comissioning other crafters to work on your house if you don't have that particular craft yourself. Or fork over a sum of money to an NPC to advance a building phase for you. (to keep the "gilsink" aspect of housing)

It also allows for materials from all levels of crafting to be used, allowing even low level crafters to make money. HQ items would make construction advance quicker.

To prevent the AH from being drained of materials too fast you could limit the amount of building progess per day.