Thank you for your kind review. I do ask all guests if everything is OK with the house and when I asked this question of your group, I head everything was good, so was not aware of the shower issue during your stay.
I wish you had let me know during your stay about the shower water pressure issue, since this can be due to the heater's internal filter which occasionally fills up. If this occurs during a guest's stay, it only takes 1 minute for me to clean this and then the pressure will be restored.
Regarding phone services: prepaid Thai SIM cards are available all around the island and even if one has a 'locked' phone from another country, second hand mobile phone are also available from a number of local shops for as low as 300 Thai baht (less than $10 USD).
All the Best,