As a veteran in this industry, there are some very important basics for you to underdstand.
Any TEFL course you do that is not
ACELS approved, is not worth the paper it's printed on - this includes all online courses currently, as TPs (teaching practise) is not offered. Personally, I wouldn't hire someone with an i-to-i certificate.
Also, as ACELS is a sub-section of the Dept. of Ed. & Science, your qualification will be automatically officially recognised in all European coutries under agreements of reciprocallity. Recognised English language schools in Ireland can only hire people who have a recognised qualification, so to be "trained" by an unrecognised training institure rules you out of the majority of jobs. There is a list of reconised training providers on the ACELS website - chose one of these and no other.
The Cambridge CELTA is one of the very best introductory qualifications available - and universally accepeted around the world. Ensure that it is the Cambridge CELTA, if paying €1400.
TEFL teaching is horrendously paid - if you are serious about it, it can be a rewarding career. However, most people use it as a stop gap - and very many employers have come to treat staff as stop-gappers. There is some sense in trying a shorter, cheaper ACELS course, other than the CELTA, and if prepared to commit to a career after a year or two, then DELTA might be the way to go.