I am a Newbie to Philly Sheriff's tax sale and need help

[Ehab Tadrous]

I am a newbie to philly sheriff's tax sale , and kept asking this question to everybody to make sure i have the right clear answer , even at the sheriff's sale i asked one of the shirreffs, but was not quite sure

Do i have to run a title search for any property i am interested in at Tax foreclosure sale , or also search it at the city hall records for any other mechanical liens , utility bills , etc...
or i do get the tax deed free and clear as some of them said ??
also if i am buying this property for a good price and planning to flip it , hold , rehab and rent it ,, do i need to have title insurance after the deed recorded under my name or no , if yes what is the benefit of it , if i am planning to sell it soon ??

or do i have to keep it until the redemption period expires??