How many dogs and what size are they? That estimate is WAY to low.
I flew two cats 6 years ago and it cost $3,300 (all in). A VERY good price would be $1500/per dog. Plus the vet visits before hand, crates, etc. The fees on the UK side are about £400 per animal.
I'm not familiar with Glasgow and cost of living, so can't help there.
But yes, the UK is very expensive. It would be very expensive to move for only one year. Moving is expensive - full stop. International moves are crazy expensive. Doing it twice potentially in two years would be a big outlay. But the dollar is a lot stronger than the pound now (and likely to continue to overpower it), so it's not a bad time to convert from USD to GBP.