WIBU to withdraw my offer of accommodation after she cancelled dogsitting?

Depends on how good a friend she is and whether you’ll miss her friendship if she takes offence.

If it's Trusted Housesitters, there's no money involved.

If you would never have agreed to it had you not required the dog sitter then I guess the deal is off.

To me I think I'd probably still say they could stay a few days, if they are nice and not difficult and I thought I'd enjoy seeing them.

But by all means say you've actually also double booked and forgot you've another guest. Or that you're actually away yourself.

I'm pretty sure you don't get paid to be a Trusted Housesitters person. Your "reward" is the free accommodation. She might genuinely want to protect her status on there or be near her relative that week, but that's not the OP's problem. I wonder if she's going to be tapping up the relative for free meals and would be tapping up the OP for the same during their weeks together - so to avoid having to pay for herself during the week alone in the OP's house, she's staying near her relative instead, and will be angling for free hospitality there.

I highly doubt that she is looking after someone else's dog the exact same week you need a dogsitter. She just doesn't want to look after your dog.

Awful behaviour on her part. Even if you did let her stay it wouldn’t be the same after this. It would be awkward and you’d resent her being there, with good reason.

“Thanks for letting me know. I hope things go well with your move.”

YANBU. She has clearly taken on the job to earn more money PLUS saving money staying with you PLUS the money she earns as a LL.

I would tell her something has come up and she can't stay.

Exactly this. I’d be really annoyed. Let her know what it feels like to have to rush last minute to find an alternative.

You are not paid for Trusted Housesitters, so if it is that, that’s a red herring. I have been cancelled on by a Trusted Housesitter with a month’s notice, so there is no barrier to her cancelling except her own wishes. As I understand it, she doesn’t even risk a bad review unless the actual sit has happened.

However. Is it a very precious friendship? Is she genuinely contrite? Would you have had her to stay if she wasn’t dog-sitting? If the answer to all three is yes, then perhaps suck it up, but be wary next time she needs something. If the answer to any if them is no, sack her off. I think the wording is “I agreed to this thinking it could be a mutually beneficial arrangement, but now the benefit to me is longer there, I’m afraid it’s not convenient.” Transactional arrangements work both ways, by definition.

YANBU. She's a CF, quite frankly.

I agree with @SillyGooseyGander . It seems very suspicious that the week she's booked herself to look after someone else's home/dog is the exact same week that you needed her to look after yours.

Do you believe her? Maybe she's not a dog lover so has arranged something else that week so she can get out of it.

not unreasonable at all...especially if you know she took the other booking after agreeing to look after your dog. If she's desperate for money she should have told you and given you the chance to pay her.
I'd say you've also accidentally "double booked"
and having someone else to stay! She can stay with her elderly relative.

I definitely think this would be your best response - make it sound like she won't be staying with you at all!

Oof, seems a big coincidence that she only has the paid gig the week you asked her to dogsit for you 🤔 but the other 2 weeks where you're putting her up for free without looking after your dog, she hasn't 🤔🤔

I would sack her off to be honest, because it seems likely that's she's engineered it this way because she's inherently one of life's takers. I wouldn't be shocked if you let her stay, that she'll not put her hand in her pocket once and you'll be back here posting a thread all about your CF house guest who's eaten all your food and drank all your drink and expected you to wait on her hand and foot.

This reminds me of a near miss of mine. I live somewhere that people consider a holiday destination, v close to beach. Last spring, BIL and SIL (who've moved out of this area to a city), proposed they stay at our house to "keep an eye on things" for the 2 weeks we are away in August. Framed as doing us a favour, rather than as them having a house by the beach rent free in peak holiday season. DH replies "oh yes, that will be excellent - we can cancel our dog sitter and save ourselves £1000." Predictably, they didn't want to look after our (placid, well trained retriever) dog and couldn't understand why we wouldn't stick him in kennels instead so they could fully enjoy doing us a favour without actually doing anyone a favour but themselves.

This. You already cancelled your regular dog sitter and now "friend" has cancelled any dog sitting time. She really dropped the ball and it's a bit much to expect weeks of housing from you when she's done that. Her housing and tenant issues are not your problem.

I hope you can get your regular sitter again.

It would be a no thank you.
Friendsship works both ways.

There’s being nice and there is being a pushover.
”Oh ok I wish I had known earlier then I would have kept Rovers original booking with the dog sitter he is comfortable with. It’s going to be tricky finding someone now at such short notice. I may need to change my plans so with things so up in the air, I can’t offer to let you use the house any more.”
It may end the friendship, but frankly I would be annoyed enough to let it fall. She has put you in a very difficult position and can’t still expect a huge favour from you.

Seems a bit petty for you to cancel her. If you take her version of events, that she’s double booked herself and it coincides with seeing an elderly relative - perhaps they have made plans to do something together.
Unless she has history for being a let down I wouldn’t hold it against her this time. (Although I can appreciate how annoying it must be for you).

Yes, but probably best not to over react, don't give her a ruff time, just let sleeping dogs lie, there may be a more serious issue behind it and you don't want to end up barking up the wrong tree.

I agree with @DearlyDiego that this is the way to go. Let her scrounge free accommodation from her other relative. Weaponised misunderstanding.

Did she offer to pay for her own food and a share towards utilities while being an unwanted guest?

No way would she be staying at mine. Very poor. You’d think it would be the least she’d want to do to say thanks for letting her stay.

I'd feign stupidity and reply something like "Oh, that's put me in a bit of a situation to find a replacement, but I'll look into it today. Great news that your [other friend/relative] can host you for the weeks you needed. All works out in the end"

Then watch her squirm when she replies that actually, no, she still needs a favour from you...and you can reply in a day or two that: sorry, the only alternative you can find for her change of plans needs to stay at yours, so there's no more room at the inn.

I absolutely am petty and I don't see why people are so worried about being so. Your friend isn't worried about inconveniencing you, so why are you worried about her?

You’d be really petty. It’s annoying but just really mean on your part to tell her to leave - surely you’d have let her stay even if you’d no requirement for dog sitting?

"Okay no worries. I'll need to sort out a new arrangement now so I won't be able to host you the rest of the time."