Sometimes you get shock loss, sometimes you don't. Sometimes it grows back sometimes it doesn't. Count on looking like crap for 6-8 months after your procedure. Some people don't believe that. I've been on the boards three years and I've had two surgeries. I've seen the non-believers flip out after their procedures because they just didn't believe they'd look so f'd up.
It's not bad if you prepare yourself mentally. Have toppik or Dermamatch on hand to fill-in (or one of the other cosmetic products). If you're light skinned, you may get a great deal of redness. Make-up or tanning lotion helps cover it up.
Try not to do a lot of small procedures unless you're doing fue/fit. Repeated surgeries mean more risk of bad scarring and more transection of donor hair (if you're getting strip surgery this is an issue, not so with Fue/FIT which is okay for multiple surgeries).
Also, the larger the procedure the cheaper it gets. The savings are substantial. A typical cost structure for strip might be around 4.50 - 5.50 per graft up to 1500 then drop to $2-$3/graft for above that amount in one procedure. So, lets say you had 5 procedures of 600 grafts at $5 per graft. That's $15,000.00 for 3000 grafts. But if you get 3000 grafts in one procedure, $5 for the first 1500 and 2.50 per graft for the rest, the total cost drops to 11,250.00 The cost differences start to really add up in a big way.
Also remember, since it takes 10 months to a year to feel good about how you're looking after surgery, you don't want five procedures. Five procdures would add up to 2/12 - 4 years of your life post surgery thinking your head looks like sh**t while you are waiting for things to normalize. If you think you're uncomfortable with how you look now, wait 'til you're waiting for your hair to grow back after surgery.
Last thought: remember, once you start hairtransplants, you will be committed to more procedures if you keep losing hair. If you are in your twenties and already think you need surgery, count on it. You will almost surely continue to lose hair and need more surgeries.
I'm cranking all this out at warp speed during a quick break from the job, so I'm skipping many important subtleties, exceptions and caveats. There are also legitmate differences of opinion about age at time of first surgery and fue/versus strip that you should spend a great deal of time reading up on. But, these are some important, very general observations IMO. It's a real son-of-a-b**ch to live with the wrong decision, so educate yourself and take your time deciding.
Good luck,
Hairnow