I count the number of tiles it prevents me from walking through. Some of the items look like they occupy more than one tile, where as they actually do not, because of the 2d isometric view of UO. The metal and wooden chests are a good example.
Stayin Alive,
BG
Exactly...hopefully Barry's explanation makes more sense, but this is what I was trying to convey.
In your picture, you have the perfect floor tile for figuring stuff like this out, and yes, the yellow box is 1 tile. I think where you're getting confused is by the graphics. Items can have a very small footprint (meaning number of blocking tiles), while having a very large graphic. A classic example of this are the trees you place with tokens. I recently customized my house and wanted to put those trees everywhere, and was amazed how many I could fit into a small area. This is because the trunk only takes one tile, even though the trees foliage appears takes up a 3x3 spot (visually) but it doesn't block placement, therefore the item has a footprint of 1x1.
In your picture, I'm not sure what you mean by "chests can fit in one tile but they never do" They very much do take up one tile. Try the elven bookcase (think that's what it's called). It looks like it's 2x1 but you can actually walk through half of it because the graphic is bigger than the footprint. Therefore it's footprint is 1x1
Find a nice clear area, drop the item, then proceed to walk north into the item. If it blocks me then that's one tile. I then move over one tile to the east and try and walk north into the object again...if it blocks me then I know it's two tiles wide....etc, etc...then if I have to, I can face west, and try walking west into the object again to see how many times I'm blocked. When I'm done, I know how many tiles wide and deep the item's footprint..
I recently had to try this with one of the tailoring looms as it looks deceptively large but really it's only 2x1 (or 1x2 depending on which direction the loom is facing). So when I was customing my house I made sure to leave a alcove that was 2x1 to accomodate the loom.
If you're still unsure, I can show you in game, just send me a PM or ICQ me at 8249606 for a faster response, but I think Barry explained it quite well.
As an aside, I believe you could use gozas to figure out an item's size. Place one goza, raise it a few times, then try to place the addon on top. If it's a 2x1 object, it won't place because part of it's not supported. That would be about as scientic as you can get. I only tested this briefly, so don't quote me on that.
