prêt avec ING?

ING being the best offer sounds surprising to me.
I would have though CRELAN or AXA being better, but things change so fast in the bank sector nowadays...

The way I do comparison is the following one :
- add total credit cost
- add life insurance total cost on 15 years (no need to index even if not paid one shot)
- add 15 yearly fire insurance cost
- add credit file cost
- add "notary cost" for the mortgage operation or for the "mandat hypothécaire" operation (if all banks require the same guarantee for the same amount, this particular point is no use)
- add any other cost (I don't see any right now)

Divide the whole by the lengh in month : 180 if 15 years.

Now you can compare the various offers you have received.

I don't think of any hidden conditions right now.  Most important ones that can be negociated if your file is negociable enough :
- no mortgage but "mandat hypothécaire" instead (or lower mortgage)
- early redemption penalty cost (legally maximum 3 month interest)
- life insurance not 100% on both heads (thus 200% cover when a couple borrows) but 65% on one and 35% on the other for instance