Can anyone advise me on the procedure for buying a used car?

I am currently looking for a used vehicle to buy and was wondering if anyone can tell me exactly what i will need to do. I know I will have to transfer the registration and somehow get insurance (and I want comprehensive). also i would prefer to get a mechanical inspection before I purchase. if anyone has any specific information about how I should go about doing this please let me know.
Thanks.
Thank you both for your answers. this is very useful to me. :))
Hi,
1) Choosing the used car there are so many sources e.g.:
a) Qatar Living Classifieds
b) Gulf Times, Peninsula & Qatar Tribune English news papers (classified columns)
c) Notice Boards in all Hypermarkets e.g. Lulu, FFC and Dasman etc.
d) Street No. 10 mostly on weekends.
2) Mechanical Inspection: Near Ain Khalid R/A (Salwa Road)i.e. German and Germany Computers etc. The negotiated charges will be around QR. 150/-. They will check mainly Engine Performance, Chasis bend (if any), Accident History, Gear Working condition, A/C & Wheel Alignment etc.
3) Registration Transfer: Costs around QR. 200/-. Both seller and buyer must together visit any of Traffic Depts. i.e. Madinath Khalifa, Mamoura, Matar Kadeem or Souq Wakif. If you people cannot visit for whatsoever the reasons, there are agents who will charge an additional QR. 100/- to QR. 200/- their fees for this purpose.
4) Once vehicle is transferred, later on can approach appropriate insurance company to convert into comprehensive insurance as well as ownership change (into your name).
hi
it is difficult to answser this qs but i will do my best coz i have good experience
first of all do not worry about registration, it is so simple after to choose car go with seller to the ...eg Madinat Khalifa Traffic where it take about one hr and cost 100 QR.
then to get used car i advice u to have look in many different places to get idea about prices for example
...... websites
...... industrial area street number 10 specially in weekends
...... salwa road where are many car showrooms
....... bulletin boards in almeera
....... etc
after that or before of all i said choose which car (i mean which company and model) you want buy coz if u go blindly u will get lost and u will waste alot of time to choose a car.
after to get idea about prices choose the car u want to buy from any where after to come to agreement about the price with seller then take it to computer checkup in salwa road( cost about 200 QR) where they will tell u about mechanical details of the car which will determine to complete the deal or not.
for more detail ask again