Veltz Meshugener: I don’t know what advice the other posters gave you in regards to your new neighbor. But something tells me that your neighbor/Shabbos guest is in dire need of a weight loss/life coach. Additionally. He could use “Sit-Down” therapy (If it is not as yet offered, it soon will.)
Also, it would be advisable for you to check all other chairs and tables in your house for stability, in order to avoid any unpleasant surprises. Especially when you have guests around.
As for asking your “friend”/neighbor to pay for the damage you have a choice. Either ask for the money or keep a friend. You can’t have both.