input credit

dear sir

I am a trader of photography equipment, my tax slab is 28% on camera and studio light.

I receive 12 to 13% discount on mrp from company, in that items my input credit are 14.5% vat, and I have no input credit on 30.06.17

I resale it to trader. and I sale it on 9 to 10 % discount on mrp.

when I entitle for input credit tax on stock then govt will give me 40-60% credit of CGST.

so kindly help me how to make bill because after GST I will have to make the bill on mrp or above the mrp with 28% GST

illustration

(My Side) Purchase
Mrp 100.00
less margin - 12.00
less vat 14.5%
=76.86 my costing

(trader side) Sale
cost 76.86
add margin 2.32
add gst 28%
=101.34

please help or suggestion me, what should I do.