Price of garage build and extension build

i am going to ask an impossible question here, and i am probably going to get slated for it..

But i am looking to move house, and i am thinking that i may have some building work done on a house that we are looking for, we haven't seen a property yet, but i am wondering what the costs would be if we get a house without a garage or extension, can anyone give me a ballpark figure to have these built, perhaps a minimum to maximum?

I know its a big ask, but any figures would be better than nothing, because at the moment i dont have a clue,

This is what i am interested in..

Small kitchen extension, perhaps 8 feet x 8 feet with a tiled roof

An average sized garage on a concrete base unattached to the house. flat roof and tiled.

A garage attached to the house with a tiled roof.

Thanks in advance.

You can get estimates per/sq foot using google.

Obviously they can't take into account any specifics, but they'll give you a ballpark figure.

You can get estimates per/sq foot using google.

Obviously they can't take into account any specifics, but they'll give you a ballpark figure.

thanks cyclone