Its more disclosure rather than exposure, honest factual reviews can be very helpful.
I’ve read several on THS where the person - be it host or sitter, has been disclosed a particular habit or fault and has addressed it under their review with "Thanks for letting me know, going forward I will aim to do X, Y , Z.
or Sorry about that, didn’t realise it was a problem.
One sitter said graciously “always willing to learn and will take what you say on board” and their future reviews were glowing.
Those that face the issue presented to them calmly, can openly show that circumstances will change in the future.
I’d want to know if the house smells, or the place is grimy or the hosts not so hospitable. Gives me an educated choice and also gives the host a chance to redeem themselves and learn valuable life skills, like, cleaning greasy areas or empty the cat litter box more than once a fortnight.
Factual reviews are vital to this community. 
Yes, factual reviews matter. For instance, a pair of hosts surprised me on their departure, warning that one of their cats would bite or scratch, depending on his mood.
At least they warned me before leaving, so I could take precautions. Would I have taken the sit had I known? Doubtful. They should’ve mentioned that before we agreed on the sit.
None of the previous sitters mentioned that in their reviews, even though we all had to pick up the cats daily to move them to and from a separate studio, where they liked to lounge and observe birds and such. One of the previous sitters had even left her there overnight, probably because the cat would try to bite if he wanted to linger.
In my review, I stayed factual and was transparent and hopefully helped other sitters make an informed choice. Because my personal comfort or relationship matters less than helping other sitters. We all exist in the same ecosystem and, if we don’t help each other, we’re all in for a rougher time. I won’t be complicit or enable hosts.
And you can be transparent and factual in reviews and get good results. Those hosts above for instance agreed politely in their reply to my review that they should let sitters know upfront. And l had put that feedback in perspective, because the rest of the sit was great.
Without public reviews that are honest, there’s no accountability.
I think I would have left the cats there as well if I was told they bite.
I always take HO guidance on pets as that guidance, sometimes you just have to alter pet care and do things your way if it’s not working for you and being bit is not acceptable.
Note: I didn’t leave the cats. I figured out how to make the sit work. But if I couldn’t, I’d give notice and leave, because the hosts created the risks by not being transparent upfront. The other sitters were complicit as well.
Sorry my miscommunication
I meant i would leave the cats as the other sitter had done in the room overnight and not attempt to move them if i thought i was going to be bit.
I understand you are really experienced with cats and would find a way to make it work.
Unfortunately, that studio could get really cold, because it wasn’t meant for living in — I think it was for art originally. All glass on one side. The hosts later told me about the other sitter leaving the cats overnight and said they (the hosts) were distraught over that. That seemed even more irresponsible to me — if your cats might be left to be cold overnight because one bites, then you shouldn’t mislead sitters in the first place.
Unfortunately, hosts can be negligent or selfish, which is why transparency and accountability are needed.
A review isn’t about resolution, which yes can be done differently, a review is information for others.
It makes me sad to see negativity towards “gushing” reviews. I understand the preference for brevity but I value longer reviews.
As a sitter I have left some gushing reviews for sits, pets and hosts that were wonderful and meaningful, and have had gushing reviews from HOs which makes me feel like all the effort and love I’ve poured into their pets is seen and valued.
To me it’s a beautiful thing when a mutual appreciation is expressed heartily. And the review is an opportunity to really communicate your thanks.
Also, when I’m applying for sits, detailed reviews are so important. I am suspicious of short reviews because it makes me think there were issues but the sitter just doesn’t want the drama or emotional labour of getting into it in the review. I am much more likely to apply for sits with gushing reviews.
Long live the gushing review! 
I don’t mind gushing or lengthy, because I can always skim. But if a review is short or missing info, there’s nothing I can do about that.
I think anything that would involve transporting indoor kitties to an outdoor enclosure by hand would be a red flag for me. I wouldn’t need to know about a bite or scratch warning. It just sounds as is like a risky situation where cats could get loose and/or I could get scratched even accidently if a cat got spooked. So a simple description of the process in the listing or in a review would be enough for me to move on.
In this case it wasn’t the spare bed. And would you say it publicly or privately? And what if on the whole the sit was lovely with an easy pet and a great location and you’d definitely come again if the dates worked and maybe bring a topper or inflatable sleep mat to help you get through the night?
The other cat was easy to move, as it turned out. I just brought one in and left iffy cat out in the studio longer.
They didn’t mention transporting in the listing, either. But when they told me about it over our video chat, it sounded straightforward. Again, that’s why reviews can be helpful to other sitters, if the reviewers are honest and transparent.
To me, reviews written by folks who aren’t are essentially worthless or worse, help mask issues.
We do paragraphs.
Pets
Home
Hosts
Surroundings and transport links
Must sees.
This gives prospective sitters an insight into most things that they need. I try not to gush but it’s really hard not to when the pets are just perfect, the home is well equipped and immaculate and it’s a perfect place for a break/holiday. And I would never bring arguments into a review. Reviews should be factual.
I would do both so I would discuss it with the HO first and then in the review I would include the HO response to my bringing up the issue. Hopefully a positive response which would show how much the HO wants the sitter to have a relaxing stay.
If its the HO own bed and they weren’t looking to replace it I think the matress topper you suggested would be a good solution. I would suggest the HO buy one though.
I would say to both to the HO and in the review how much I had enjoyed my stay and that I would definitely sit again if this small but very important issue was sorted.
Risky.
You risk getting a revenge review.
I don’t know what kind of HO you have experienced but without exception all of mine have gone out if their way to ensure my comfort while I’ve been in their homes
They have all asked during my stay if everything is ok for me and encouraged me to say if I need anything. For my repeat visits they have asked if I need anything different for next time now I know their home and pets. They have all been lovely people. I don’t think for one minute that if I had said to any of them :
Actually your mattress is lumpy and i didn’t sleep very well because of it, i think you might need a new one
That they would take offence and write a revenge review.
Maybe the HO on here could comment on how they would respond to a sitter raising concerns
But if i did get a revenge review then I’m a fully grown adult i can take it. I’d simply write my reply and move on.
I once had a mean-spirited HO.
It is not the past sitter’s responsibility to protect me. It is mine. Whether or not the sit was satisfactory to them is neither here nor there. It is one person’s opinion. No more value than that.
No two people have matching standards on anything. Something as simple as wiping the counter can lead to issues or where and how to walk the dog.
Those sound like some serious infractions indeed. Personally, I would refuse any task like that. On another option, I am retired so workspace is not needed but if you work digitally, then the kitchen table is unacceptable. I have found that requesting and reading the guide can expand your understanding of expectations. I too have had wonderful sits so far but on a recent one, I discovered that my definition of walking paths and the hosts definition were very different. I did take time to discuss this with the host after they left and make alterations as necessary so that they were kept in the loop.
I think cleaning is the hardest item to match since everyone’s definition and priorities are different.