You might also compare Job Security between the two places....just how long will that Job in Nigeria last?
Is your job in the UK pretty much safe as Houses?
You have a family to provide for....long term.
Could that job in Nigeria just be short term?
I know which way I would go....and it would include my local Pub seeing me as a regular Customer, my Kids seeing me every night, and my Wife having to be darned careful about meeting her Boyfriend.