I tried looking this question up but there were no questions like this I think.
Anyways.. I wanted to know if this was even possible because I know you can move things with CFrame. I have always used Size in resizing an object. but every time it resizes it, it will move the part's position if it something is in the way. I would provide code if i knew how to do it but I have no idea what to do. Sorry! Thanks for helping out. (Side note: Not asking anyone to do this for me, i just need a wiki page or maybe a little code)
What you could do is first "cache" the part's location, then resize it, and finally move it back to where it originally was.
local part = ... local partCFrame = part.CFrame -- Save the part's original CFrame part.Size = desiredSize -- Resize the part part.CFrame = partCFrame -- Reset its CFrame to its original value
Now, I realize this isn't resizing a part using a CFrame exactly, but it does fix your problem of parts moving out of the way and stuff.