3. I'm still stuck whether to stay in UK or go to the US, some people say US is miles chapers, others say that when you take into account travelling/living/conversion costs it ends up being about the same. What other options are there, other European countries? Or what about South America? Asia? I'd imagine if something exists out there it would be a lot cheaper over there?
There isnt a simple answer.
The cost equation is made up of a number of components some of which may apply to you and some may not. For example, if you earn £100 an hour endless trips to the airport with lessons cancelled due to weather may make the certainty of flying in parts of the States very attractive.
In short you need to do the sums. The actual cost of rental in the States was significantly cheaper, the gap has narrowed, but it is still less. However, you may need to add loss of income (while training in the States), cost of accomodation and travel to the States, additional training back in the UK to deal with local club / group rules and our grey weather etc.
In short the headline cost is less, but the overall cost may be more. You need to work the sums for your own circumstances.