Best Current Telephone Tarriff

Hi

I need to make about 10 phone calls per day, mostly during the day time. I used to use AIS "buffet" to make unlimited calls but now the mobile operators have stopped the buffets

I call within Thailand

What is the current best tarriff? I make 10 calls a day for about 5 mins each.

Is it worth getting a landline, are the calls cheaper? There used to be something where you dial 1234 before making a call - is that still good - how much does it cost?

In my area I can get a phone line with TOT, or TT&T. Does a fax machine work with TT&T (it is a digital line i think).

Thanks