@Lorena596 You'll get the hang of it. It can be a big learning curve. I hope she doesn't give you anymore grief. I love your "if she doesn't like it, no one is forcing her to stay and she can go to one of the many places she said she saw with a "better price, and closer to the beach". Perfect attitude.
You should not communicate with guests by Whatsapp. Especially when a guest is making complaints and harrassing you. You should keep your communication on the Airbnb messaging, so there is a record of what was talked about should you need documentation for Airbnb to look at.
I see your grandma's place, your listing, is close to me, in PV. What area of town is it in?
You should work on your listing description- it really doesn't give much information, which can lead to complaining or disappointed guests. You need to paint a word picture for guests of what to expect. Describe the interior space more, talk about what the area is like, are there shops and restaurants close by, how far it is from the beach. I do like the part about your grandma attending to her plants.
And that bedroom could use some TLC. It looks quite barren. A bedroom should look and feel cozy. One of the things that drives me crazy in Mexican places I've stayed is no reading lamp by the bed. And a bed for two people needs a bedside table on each side of the bed, and a lamp in each. Some art in the walls, a colorful throw rug on the floor.
There's nothing wrong with a simple place, but if you jazz it up a little, which doesn't need to cost a lot of money, and raise your price a bit, you'll get better, more appreciative guests.
