People have requested that I post the rental agreement template here so here it is. The template was given to me by the Delegado. It can be modified to say whatever you and the landlords deem necessary and are in agreement with. You can also add another "annex" (addendum). The document is 9 pages and it is advisable to make 3 copies - one for the lessor, the lessee and one for the Delegado to keep in his office. If your landlord only speaks Spanish, you will need to provide an additional 3 copies so each party has one in each language. Makes for a lot of signing. I used google translate and it was pretty accurate. I put into a google doc and I hope you can open it - I'm not terribly tech savvy so let me know if it doesn't open and I'll try another way. If I can help you further, message me. Good Luck!
https://docs.google.com/document/d/1g2yZiCb77khl9IBSJOEPj5RZk_2FmNgRqVBkN2JcsXg/edit?usp=sharing