Yes - the combination of those three factors.
And some British prostitutes are lowering their prices due to market forces. A girl recently told me (in confidence) that she just wasn't getting any business at £200/hr. This is the way the market is supposed to operate.
I believe that the going rate has dropped in the last couple of years in London (sorry I can only really comment on London) from £150/hr to somewhere between £100 and £120/hr.
I've noticed this in London and the surrounding counties. I agree on your estimated average.
I chatted with two British prossies I get on with very well, post punt, not so long ago. Both told me that Eastern European girls are now having a major and negative impact on the number of customers who walk through their door. In particular, the Romanian girls. And in one case, this is despite those same girls operating over 20 miles away from her location!
To me this is proof positive that many customers are now voting with their feet. The irony of both British prossies complaining about a lack of loyalty, wasn't lost on me?! These are the same type of women who would bin a punter at the drop of the hat, with some shitty excuse, should another punter request 3 hours, as opposed to a 30 minute or hour booking! I can't say I really give a shit!
It's a battle that they cannot win. Whilst by no means ancient, they're not getting any younger. Meanwhile, more and more younger girls are replacing those who were once their age, offering a wider variety of choice, services and competitive pricing. This is how the market should work, as long as quality is maintained and I believe that it is because I punt the same women! Both of these women have dropped their prices significantly, but then I already had a discount, so it's dropped to nearly that level anyway!