notaire

'I heard you should get a notaire first.' Absolutely right.
'Then I'll have to pay the notaire everytime I go to him for advice etc.' Absolutely wrong.
The charges for buying and selling property are set by law and are fixed. You can call your notaris as often as you like for advice and the final bill will be exactly the same.
When you have organised a notaris - sooner rather than later - get their opinion on the paper which you have already signed and what are the implications and don't sign anything else without running it past you notaris first.
And talk to your bank to get some idea of what kind of a loan they will give you BEFORE looking at any more property. You are wasting your time if the bank is not going to give you a loan on a property that you choose.
Good luck.

Second Kasseistampers advices ..and here come mine:

1) Sample ALL information on buying property in BE first, BEFORE YOU DO THE NEXT STEP ..the legalese side is difficult / different to your home country / language ...and mistakes can just cost you a lot of your money now!
2) www.notaire.be - look for one speaking your mother tongue, request also all legal paper drafts in your language ..BUT you will have to sign in French or Dutch (or German, if leaving in the Eastern Cantons), that's the binding document, nothing else.
3) DO NOT SIGN anything you do not understand 100%!!! NEVER!

4) the advice on talk to your bank first (or shop around with a broker) on your kind of loan / finances is absolutely necessary. your bank will also give you addresses of property experts for your evalution of the target (we paid about 3 x about 200 EUR for an evalution until we found the right one).