Accomodation - Dependant visa

Hi

I have recently got married in Pakistan and want to apply for my wife under Tier 1 dependant but have some cofusion regarding accomodation.

Currently i am sharing a two bed flat with my sister and her child and the rent agreement has both mine and my sister's name but as the accomodation will not be enough for another person, i am planning to get a three bed house soon. My questions are:

1. Does it make any difference if the rent agreement is in both names. I can get the new agreement in my name only if there is any problem.

2. Secondly, I pay the current rent fully and my sister contributes some money in cash which is not shown in my bank statement. Is that a problem. Can HO have any concerns about its impact on my elligibity to support my wife without public funds.

3. Can i apply for my wife soon after i move to the new premises? In this case all bank statements will be addressed to the old address. Do i need to wait for the first bank statement on the new address.

4. Any advise on the accomodation related issues will be very helpful.

Thanks

1. No.
2. No. How will UKBA know that your sister is contributing to the rent?
3. IMHO, address on bank statements is not important.

regards