Hi, guys thanks for all the advice.
Despite claiming FIS we would be comfortable on my salary alone regardless of no. Of children as we are quite prudent and have an older model people carrier hence no car finance or other loans. As stated our only loan is the mortgage.
We always planned to have a big family as we both come from big families, that said we always thought we would upscale to a big house long before now.
We will seek the advise of a few mortgage brokers.
Crazy to consider that back in the boom my bank tried to convince me to purchase another house as an investment !