Vircho  

Yes it is always recomended to galvanise, seeing that it will prevent rust up to 15 years and longer.

Does not matter how good the paint is, tubings rust from the inside out where you cannot paint. With solid steel bars paint can be used but with fencing where you use tubing I do not recommend it, you will have to replace within the next vife years

Depends on the quantity of work but it ranges from 7 to 14 days until installation