For the purposes of issuing a slight correction. It seems like there is 1 main applicant and 3 dependents, which would break down as:
1 year:
- Applicant: £624 (IHS) + £167 (fee) for the stage 2 visa
- Dependants: £624 (IHS) each + £623 (application fee) each = £1,247 or £3,741 for 3.
A note on dependants too - there seems to be an oversight in the system which charges for half-year more than quoted, see this thread so expect to pay around £312 more for each dependant. That would be refunded later as far as I’m aware.
So one year would be £4,532 for four people.
That being said, 5 years would “only” be:
£6245 + £167 (main applicant) + £62453 + £6233 = £14,516 (or £15,452 if you account for half-year IHS overpay)
It’s slightly over 3 times more than 1 year due to a high cost of the application itself.
P.S. If you chose to apply for a shorter period with the goal to extend once you’re there be advised that you’ll have to pay that application fee every time you extend. The IHS fee can also increase throughout the years.
P.P.S. As for my opinion - that’s a hefty sum to shell out in one go, but I myself with my partner ended up going for a 5 year commitment off the bat. In general, if you can afford it without decrementing other needs and are sure in the UK as the long-term place to stay then I’d say go for as long as you can