Is 18000 QAR good in Doha?

Some labours earning as low as 750 riyal or dirham/month.
18k is not a bad deal.

It can be more than enough or barely sufficiant, it all depends on the accomodation, which will take a big chunk of your salary.

Can you suggest that kind job to me..

Hi.

I guess 18k is good however it depends on the kind of lifestyle you want to maintain. Family expenses are too high here if you are married, have children and  want to bring them here. Accommodation n school fees are very expensive in Qatar so you have to make your choices accordingly.

Let us know if you want to know any further specific details like rents n schools fees etc.,

Regards,
Kashif

QAR 18,000 is more than enough for you being single as you said....but the aspect of self visa, self air tickets makes the whole employment sound strange to me though. It doesn't sound familiar that any organization that will pay that much will deny you those benefits. Kindly find out more about the company before moving in. Just my opinion anyway