Boxing in under stairs/ PICS

[Gamergirl86]

I'm wondering whether to get someone in or DIY this job. Boxing in the under stairs. I don't know much about wall creation and what i do know is from YouTube.
Frame, stud wall, some kind of access. If I'm honest it's a bit beyond my skill.

Anyone who is better acquainted with this sort of job have an idea of how much it would cost;

1. DiY?
2. To get someone in?

Many thanks

I recently had this done.

I had a quote for the fancy drawers set up - you know the fitted drawers that pull out, about 6 in total plus a door. That came in at. £1350.

I went for something a lot simpler in the end - a stud wall with a door in it. That was done for £800. Using soundproof board and rock wool though to help with some sound transfer issues I have with a party wall.

Manchester area.