I placed a plot a couple weeks ago.
In the time since placing I realized I could expand the size of the plot and move it over a couple tiles. The problem is the house is full of items and I have no other place to put them.
So what happens if I drop the plot with the items in it and immidiately placed a new (larger) plot on top of it?
Items no longer block placement like they once did. Theoretically, if you drop a house, all of the non-deeded items are *supposed* to move to under the house sign when a new house is placed (the deeded items poof). But, don't count on it.
I was in a similiar situation and, due to how heavy most of my containers were (pre-commodity deed box), had no means of safely securing all my junk while I resized (pre-resize actually, it was more of a drop-replace). So, I took the chance of just dropping and replacing, crossing my fingers that the items would do what they were supose to, bounce under the sign, and I would quickly drag it all back in and secure it.
Nope! Absolutely everything vanished. I mean, vanished! After waiting in que for four hours, I finally got in-game support. No one (GM's) could find any sign of the items. I spent two more hours typing back and forth to GM's who worked on the problem and tried to find the items. I can't even begin to tell you how much I lost. None of it was recovered. I attribute a great deal of the loss to my own actions, but will always wonder if the items went to some invisible spot and decayed while I waited in que.
Horror story number two: When resizing a "properly placed" house in Vesper, once the house was dropped, the terrain changed underneath so the house wasn't able to go back - my vision of a little bit bigger of a house went to no house at all. So, in addition to watching out for your items, you also have to watch out for the landscape.
My absolute favorite though was the bug years ago (like publish 6 or 7, lol) when no one was able to place at all after the publish. The deed (ha ha) was in my backpack and I had recruited a friend to stand guard over my three secure boxes while I quickly switched my houses out. Wouldn't you know it....at 4:30 in the morning, I'm in que begging for assistance in getting the new deed (house) down. The following day, Origin (ha ha ha) noted that there was a bug in the publish that left players unable to place houses, warning them not to re-deed their houses until they fixed it (little late for me). I lost everything I couldn't get into the bank, which, was, well -- just about everything, short of the itty bitty house deed that proudly went into my backpack when I re-deeded the house to put down a new one - talk about salt in a wound - two deeds, no house, and items at your feet you have nowhere to store (all of which happened when UO was in its prime and you were happy just to find a spot big enough for a 7 x7 and your friend could have 25 items in his/her co-own box, woohooo!).
So, I guess you have to ask yourself, do you really want to take the chance? If you do, I suggest you at least move your items to a few tiles away from the tiles that are designated to your new house before trying it and bank your most valuable items.