Broken pipes cause tenant not to stay in the property

[Yusuke Koike]

Hello,

My name is Leo
One of my investor friend has an issue with his rental property (2 story townhome with HOA)

What was happened to him and the unit is
1) the drain pipe on 2nd floor bathroom was broken
2) water leaked in the 1st floor ceiling and walls
3) in contractors opinion, this problem was caused by just normal wear and tear (already 40 year building)
4) Those pipes are not shared wish other units (service the unit only) and HOA won't do anything or take care of it.
5) it will take 1-2 months for everything to be fixed up
6) Tenant will need to evacuate to a hotel or shelter 

I have two questions,

#1 In this case, whose insurance should cover the fee of tenant's hotel while the damages are fixed up? (owner's insurance should cover?)
#2 If the pipes were shared with others, does HOA have to take care of the issue?

Leo