[heavenlyblue]

Here in the UK I think it takes about 10 days to obtain the certification to be able to install AC, plus the cost of approximately 1 AC unit. Installation costs are about 2-3x the unit price, so it's actually massively cheaper to get certified and install your unit than wait for "the professionals"

[dlkf]

Assuming you value 10 days at the cost of 1-2 AC units.

[Cpoll]

If it saves you a single $8k "we have to replace the entire thing" grift, those 10 days can be valued at about a $200k salary ($4k a week).