no
It all depends on the model of the BB gun. There are over 300 different modal BB guns. Which one do you want to scope.
Find an authorized repair center
Pretty much outside the scope of a hobbyist
Sling, Bypod, Scope, Flash light, Laser.
The scope on the R73 is a fake scope. It really a see through Hopper. You can not replace it with a real scope. You have to use it to fill the gun with BB's.
It all depends on the scope rail. The scope is designed to fit on a metal rail. If the rail is plastic it will come loose while shooting.
Different type of recoil impulse
on top of the scope is the brightness and on/off switch. the top of that comes off when you twist it and the you put your batteries in there
What condition is it in?
It all depends on the Daisy Scope rings that you have. The M4 has a removable front and rear sight. This will allow you to add a scope to the Weaver rail mount on the M4 if your scope rings are the weaver size. If not, then you need to purchase weaver scope rings for your scope.
For its intended use, a scope is not needed. You will spend more than it is worth to have one mounted after you buy it.
If its a BB Gun, Then Yes.