I think the Arch-Mage's chest is strictly for ingredients that you want replenished. Seems I remember being told not to leave stuff in there more than a week or it might disappear.
I ran across Gro walking down the street in Skingrad. Had decided my two houses, one in Cheydinhal and the manor in Anvil, were quite enough. I was forgetting what I had at each house. However, I do like home decorating and I had scads of money, so Skingrad seemed a nice middle of the country location for a third abode!