Average cost for spouse petition. ?

Spouse had been in the us since 01 , entered legally. Has been in the us since then. Filling out paperwork terrifies me as I don’t want to make any mistakes and delay processes I am a us citizen he is an undocumented immigrant. We file taxes together We have a child together Who He came here legally at the age of 10 And remained here.

Howmuch does it cost to file for me petitioning on his behalf through a lawyer ? And how long does it take to get approved and get workers permit ? Howmuch does all this cost through a lawyer? I got a consultation and a lawyer was charging me 5k for the entire process is this a good price ? I am in Dallas tx