Hi. I want to state some of the things that others have mentioned. If you want to restore some of your lost hair finasterid and minoxidil is the first options you should use. Please look at my profile and se how much hair i restored with those products + the rest of the things that are listed in my signature.
I was told by many that i was not a candidate for hair transplant but i ended up only needing 2700 grafts to get a very good density and a full head of hair. So like you i had severe hair loss but i think that yours is worse than mine were. But you still have some hair. You have all the characterics that could give a very good result from those products beeing young and having lost a lot of hair.
I think that if you havent tried this then your plan to undergo such a huge procedure is to say it mild not a smart thing to do.
I have seen some of Umar?s huge sessions not in person but on pictures. I think that when using a high number of body hairs your hair would look artificial and it would be quite obvious you had a hair transplant. I dont like the look of any of the huge cases i have seen from him.
If i were you i would start on minoxidil and finasterid and then reevaluate in 8-10 months time. Then if your situation have improved i would see if there was enough grafts in your donor region to get a full head of hair. I would try oral minoxidil. If not i would simply shave my head to see if i could settle with that. If that doesnt work you could think about this plan again.
This plan should only be your last resort.