Ebrahim;

Listen carefully. First of all, if you can (and I doubt that you will) find anyone that will allow anyone on this planet to take "their" jumper out and demonstrate for you how their horse jumps "cold", that is without a good long warmup, depending on the horse, then run like hell in the other direction.

As well, those "some people" who told you to do so?....run like hell from them as well, as fast as you can in the opposite direction. Their advice, you do not now, nor will you ever need. They know nothing about horses.

Next, if I want to sell you a horse that is gimped up and needs medication to jump, its not going to be an oral pain killer that is being administered, that will just get him "stoned" (drugged up) and groggy and I need say no more do I? However, what I have seen done is local pain killers being injected at specific sites in the hoof such as, lidocaine and bupivocaine in order to have the horse be able to jump. Trust me, when I say that, if that is happening, you sure as heck are not going to find out if it is. Unless you wait around for some time for it to wear off. The seller is not going to let that happen.

My obvious impression is that you are very anxious to start jumping and now!! So, my very strong advice is that you take jumping lessons from a very reputable trainer, 2 years or so and then consider buying your own jumper using the knowledge that you will have gained.

Or, if you simply cannot wait, and if you have the money, then buy a really good jumper prospect that has been started out by someone knowledgeable and get "qualified" instruction on this (your own) horse.

Good advice from Paul there; can I also add

1. Take someone with you who is not as eager as you are so they can spot any problems and keep you focused :-)
2. Get soemone to video you riding/jumping the horse - I was sent a video about a "problem" horse recently and told them straight away that the horse is in pain so no wonder he is grumpy; his front end went over the jump ok but his back end came over sideways and twisted! Take the video home and watch it carefully before making any decisions.
3. Get a full vet check so that you have some insurance if you need to make a claim after you have bought him (what this costs you can be "haggled " off the price of the horse s it is money well spent).
4. Take photos of any problems/skin marks etc. so that noone can say you have inflicted anything on the horse if you return it
5. Pay by credit card/paypal or some other protected means if you can (I realise not always possible) but it does help to give you extra protection
6. Check his passport thoroughly - how many owners has it had, how often has it changed hands - if every year, walk away.
7. Write down a list (no matter how long!) of things you want to know so that you wont forget and wont get caught up in the emtional bit - make notes about the answers and take particular note of anyting they are vague or don't know about
8. Make sure that their reason for selling it makes sense
9. ask for his vets details and permission to get the medical records - check everything matches up
10. Do NOT fall for the line "Well, there is someone else intereted in him, so you need to decide quickly" - don't be pressured, if he's yours he's yours, if he's not, so be it.

Think thats all for now! I know it seems a lot but (a) this is an expensive purchase; you wouldnt grab a car just because it looked pretty, think of buying a horse in the same way. (b) Genuine people will not mind all your questions, fraudulent people will - if they start getting irritable with you, walk away.

My Dad had a saying whenever I wanted to buy something, "Take your time and don't worry if you don't get it; where there's one, there's another"

Ebrahim,
You've been given such good advice from Paul and viccihh, I just want to raise my voice to chime in. Esp. in Paul's last two paragraphs there.
I would like to add this; If this is your first horse, or if your own skills in jumping are novice; look for a sound and steady horse that has years of experience and can be your teacher.
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Also, I was shocked at the advice to jump without warming up! That must be one of the worst piece of advice I've ever seen. If the horse wasn't sore before, he will probably be after that kind of treatment.
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I wish you the best of luck with your search, but also hope that you will take your time. There is absolutely no point or gain in getting a fancy jumper if you two don't get along or you can't ride it well enough to get the best jumps out of it.

thanks alot every one
well i should say i am jumping for 10 years , surprising :), yet the last experience, the last horse i bought, was just bad. and i am anxious now.
secondly, this is the first time i can get information from an online Uni so i want to learn as much as i can and this is great. i dont want to go through that pain again. Every single idea opens a new window for me so i appreciate your helps and unfortunately there is no insurance here and i lost my trust to people who are around so it seems i should go this way alone but no matter how expensive or cheap is the horse i will get a full vet check.
thanks again appreciate your helps