Charging rent to friend

[Deadsouls]

I'm not sure if this is a WWYD. But couldn't find the relevant section.

I have a house in London (zone 4), and am renting out the double room to a lodger. The lodger is a friend who wanted to move to london.
She's a student and in a moment of feeling generous, (or codependent) ended up charging her £360 per month inc. bills. This was because it was what she could afford.

Anyway 6 months down the line - I'm suspecting that I'm undercharging for the room. Another reason I charged less is because I'm a single mum and live with my 2 kids (9 and 6), so it's a family home and the kids wake up early, can be noisy etc. So I thought this would mean that the house would not be an attractive prospect and I'd have to charge less to compensate for house, early waking etc.

Now I'm thinking I will have to broach the subject of raising rent with the lodger. She knows I'm helping her out. She said when she earns more, she'd pay more but that doesnt look like that's happening anytime soon.

I found out from 22 year old niece that she pays £480 per month plus bills for a smaller room.

At the moment I feel I'm taking more care of the lodger's needs than my own.
WWYD

Having someone who is friendly and gets on with the kids and isn't annoying in the kitchen/doesn't hog the shower when you need it, is invaluable in a lodger.

I'd probably ask for £400, but maybe discuss it as something to raise to in about 6 months time? FWIW mine pays £450 for double room in z3, own fridge-freezer, includes bills plus exercise routine from enforced dancing with 4yo...

Previous one paid about £300 as the room hadn't been done up yet, a 2yo is much more annoying, and was usually unemployed - it was fine for some months but eventually asked to leave as was just a bit annoying and we probably wouldn't have stayed friends if we'd stayed living together.

Blame both and double it lol