Renters and Dolby pool

[Darlene Bustamante]

 I live on a 2 homes on a lot with my owner my landlady in the front house me in the back,Okay I got permission from my landlady to go ahead and put up a 16x 48 in pool then she's later comes to me telling me I need to get renters insurance and I need to put a gate with a lock.  Mind you the only way to get to this area is behind my house. She then tells me to put it all in writing when we verbally discussed this before I purchased the pool. Do I really need renters insurance.. Whast do I do what am I responsible for?