I need an EA on mt4

I am willing to find a mt4 programmer to help me out to create an ea. I bought one which works great and I would like to have one with my one code. I guess its actually pretty simple, it's a martingale based expert advisor, I know all the variables I want to include and how the ea I'm currently using works but I still don't know how it decides to place the TP once orders reach several levels of the martingale.
Kind regards
Daniel