Not sure where these should go, but an trying here.

Ok, my husband will be going to Queens in Belfast.
He has student loans but will not get them until 3 weeks after he gets there.
Once he gets there he will need to find an apartment for us (wife and 3 kids).
We can't get apply for our Visa's until he has an apartment for us right?
So, the question is?
How much cash should he take with him? And is there a limit on how much he can take though customs?
How much will he need to get an apartment? First month rent I assume, hooking up utilities etc.
And how much will he need to live off of for 3 weeks, food, bus fare ect?
Also, anyone have links with places to rent near Queens?
Thank you so much!
~Mary