Hi, you said you're a single guy and then: ".....would you know what salary i should negotiate for as a married couple?"

You should know that in Qatar, you would only be considered as a married couple if you were actually legally married, i.e. you couldn't ask for married couple allowances on the basis of bringing along a partner with whom you cohabit.

If you're not legally married, then your partner would need to get a job and work visa/residents permit in their own right. Or, alternatively, they could get a tourism visa, and keep making visa trips to one of the other Gulf states.