Do Tier 2 Dependants need to apply from their country"u

[h_a]

Hi Guys
I am on tier 2 visa for last 3 years and getting an extension for another 2 years
recently got nikah / marraige certificate and now i am ready to apply for my extension
my question is when i am applying for extension can i apply for my spouse visa dependant application at same time or they need to do it from pakistan where they actualy living
please let me know

[h_a]

and also how can they show enough funds
can i show i have enough funds to accomodate both of us
and if i can is the requirement 900£ for me as tier 2 general and 600£ for spouse?
so 1500£ in total for 3 months?
please reply