But what low price can I offer that might be accepted rather than
paying too much. Maybe, they are anxious to sell and will accept
a low ball price, however, I don´t want to put them off with an
insulting offer. Where to start to see what they will do? Your
thoughts and experience is appreciated.
Do some very local research by comparing listings, or even looking at similar offers. If the property is Mexican owned and you insult the seller with a 'low-ball', they may not even talk to you again. So, it will be important for you to try to make your first offer in a 'reasonable ball park range'.
The ad lists the owner's e-mail and says you can arrange a showing - ask the owner if you can meet them, see the place and talk with them. Treat it as making a new friend and be human about it. After getting acquainted, ask them why they're selling, and what they plan to do after the sale or what they'll use the money for.. that way you might discover their motivation for selling.
You don't have to make a thorough inspection or make an offer on your first visit, and they may give you some hints as to what they would consider acceptable. At worst, you'll see the inside of the house and lose a couple of hours.