Came across this while looking for something else...
http://www.sweethome3d.com/
A free, open-source program, apparently Java engined, it seems quite nimble.
Haven't tried the program yet, but it claims to import OBJ, DAE, KMZ or 3DS formats. Also, if you dig around in the on-line info, this claims you can export a scene render as OBJ + MTL, allowing re-use in eg Blender or, potentially, Poser...
A couple of limits it admits--
Memory limit of ~ 2GB, IIRC.
No pitched roofs, so fake flat-roof or add to exported model.
No arched etc ceilings, IIRC, but I used my DIY arched modules to get around the same issue in FloorPlan 3D...
IIRC, the plan format is proprietary, but being able to export scenes as OBJ+MTL could be neat...
I'd suppose that 2GB limit prevents using detailed figures in scenes. I've some very-low-poly 'static' folk from my 'FloorPlan' days, so I'll give them a try...
Um, there was something else, but I've just been distracted by a quorum of low-flying cats...
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Hope your New Year celebrations go well; Here, the storm's blown through, the temperature is un-seasonally mild, but bursts of heavy rain mean our cats are sulking...
Nik