Old/new dishwasher

how much to detach my old broken dishwasher & attach my new one?

Rates from wherever you bought it are usually fine, as they will also cart the old one away.

Ahh, but my current one was gifted as well. Trying to see if I can get it done for less than $175.

Check out some of our local handyman services.  Installing a dishwasher is not rocket science, but some familiarity/experience with the process would be preferable.