What does the term 'Affordable Housing' actually mean?

We KEEP hearing this phrase banded around every time the price of housing is discussed.

Yet I've asked many times (including on here) what the phrase means & it's a question guaranteed to be ignored.

I want to know what 'Affordable' housing actually costs.

In other words how much money do I actually have to have to be able to actually afford one?

Because lets face it, all houses, just like all private jets & luxury yachts are affordable. You just have to be able to afford them.

BUT NO ONE ACTUALLY KNOWS WHAT THE DAMN THINGS COST!

So if we don't know what they cost how do we're know they're affordable?

I don't even know if they're houses for renting or buying outright, like on a mortgage.

If they're rented houses does the phrase mean they're owned by housing associations who charge rents coverable by housing benefits if you're unemployed? A bit like council houses were before our tory governments (for whom more houses than the rest of us are affordable) sold them off.

Especially I'd like to know:

1.) If affordable houses are buyable outright what is it that marks them out as 'Affordable' (as opposed to affordable only if you have enough money)?

2.) If affordable houses are government or council or housing association owned & rented what do they cost to rent?

3.) How do I find out where affordable houses are?

4.) At what point in my income or savings am I'm discounted from qualifying as someone affordable houses have to be affordable to?

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