If your insurance expires before your visa, you've not met the visa requirements and you will be on overstay from that time on. Suggest you make appropriate adjustments. To don't want overstay on your record.
Go to the bank prepared. Have copies of all needed documents neatly in a folder. Residence certificate, passport pages, 1yr lease agreement, etc. Dress somewhat professionally and be respectful. Your goal is to make THEIR job as easy as possible.
Cost of living difference is about 30-50% depending on lifestyle and activities. If you play golf it's about 120% for comparable quality. Healthcare is about 30%. Health insurance is about 70% but quality and payout vary widely. Many choose to self insure.
the will prevents a long probate period upon your death. Even if a beneficiary is listed with the bank, the account will be frozen until probate completes. A will in the hands of a lawyer will ease that process.