Depend on if you are making a legal rental or not. Legal rental units require that the panel is accessible to both parities, or you have 2 separate panels, so you may have to get a new panel somewhere which is a good idea anyway so you are not running new wires to your old panel which is probably full.

You will need to make sure there is proper egress from the bedroom.

The connecting stairs from the basement to the upstairs will need to be removed.

We did our recently for about 45K. Including electrical heavy up, all new wires, HVAC (a mini split), install small ikea kitchen, some wall demo, 2 new entry doors and a new window, laundry, flooring. Bathroom was there. Could have been done cheaper but the cheap windows and doors kill me.

we did it for 18k about 6 years ago. No permits though and pretty basic, but it included putting a full bathroom in (there had been a hook up).

$25,000-30,000 for 1000 square feet, no finishes basic bathroom

Contractor . Basement is in good shape but is not finished

Contractor . Basement is in good shape but is not finished

DIY or contractor?

Building on a recent thread ... How much for a low cost basement finish that does not require a dig out?