Swingsets and small pool - rental agreement mods?

[Kelly G.]

Greetings

My tenant wants to put up a swingset and small 'kiddie' pool for the grandkids in the back yard.  I have no problem with this.  I am wondering if you modify the rental agreement with legal precautions/safety/liability (?).  Or just give written approval  - per existing rental agreement.  

Thanks in advance

Kelly 

sfh/ Milwaukee