If I was to add some layer of fiber glass to my kit how much will that cost and will that make it a tad stronger?

 

That wont work, unless you are refabricating the whole kit. Even if you do so, that doesnt mean it will be that much stronger. the money you spent on doing that might cost more than buying a new bumper. You should consider getting a kit made by something else besides FRP.

 

I was thinkinga thin layer nothing major.