THS may not be the best option in this case, as THS sitters generally need confirmed dates in order to plan ahead.
In addition, on THS very short sits (such as one night) tend to be less popular, since sitters now pay a £9 booking fee for each sit on top of the annual membership fee they have already paid.
You might consider advertising locally to University of Bristol students instead, either offering the sit as free accommodation in exchange for pet care or as a paid opportunity.
Many thanks. The most clear info I received. Yes, my needs are one night here and there sometimes more, sometimes last minute. So sounds like this site is not for pet sitters. I also need to interview people before they come to my home and look after my cat, so with this site, it would not work, especially for one night cat sitting.
No, I haven’t reached it by mistake. If you read my post, you will see.
How is it confusing? It says quite plainly what I need and seek answers to. What did you find confusing about it?
No chance. Full of dog baiting groups
How long before do you know the dates? One week or more before = more likely works (if your sit is attractive and someone is free and looking). Shorter notice = might work, might not.
I recently sat for one cat in Bristol. It was one night, and I got into contact with the host one week before the night. Worked great for me (and for the host). Yes one night is not much to explore Bristol, but I still got the feel, enjoyed just to walk around the corner to the nearby super market, seeing the colorful houses, a little thing here and there. Would love to visit it again. (I am a bit of an exception because I pay flat rate to all train travel, meaning that I can easily be today in Bristol, tomorrow in Glasgow, and then in London, and it costs me nothing more - travelers who need to pay their travel costs are not so keen on coming for one night).
The host did not interview me. Many hosts do always interview. These instantly accepted my application. If they had taken more than 48h, I would have probably found something else - it was very last minute, I needed that one night, and I am very popular. I think with last minute and with short sits you will need to trust the website, the previous reviews etc. It sounds to me like you do hard to trust on people (no judgement - just that it can make using THS very stressful and complicated), so THS would probably not be a good fit.
Also with the new fee per sit, sitters will not want to do short sits. You can combine: a neighbor teenager for one to three nights, anything longer try to get a THS sitter.
Why would I pay to advertise if my needs are what I asked in the original post? No specific dates, sometimes one night only. Hence why I asked advice, you see?
I am not sure I would go to all that effort for random one night cat sits, but thank you for your answer.
It won’t probably suit all your needs but it could work as a complement, for longer sits. You can also sometimes get sitters for one or two nights but that is more difficult, especially if it’s a last minute thing.
Also, no one in the platform will commit for all your needs on a regular, flexible basis. On THS we usually confirm sit by sit. Sometimes owners publish several dates but, most of the time, different sitters apply for different dates.
I hope this helps.
How will anyone know the details of the dates/responsibilities/location/amenities etc if you don’t become a member of THS (here you’re ONLY a Forum member) and advertise your listing by linking it to your profile.
BTW sitters also get to talk at length via video chats with pet owners to see if we can get along with them, it’s very much an equal matching service. I hope this helps.
You need a local person that you pay. Between your varied timing requirements, needing someone who can drop out of their life and into yours for varying times and often at short notice it is extremely unlikely you will find this on THS. Even a local paid person would not necessarily be available every time you need them. Think about from the sitters perspective, why and how could their life revolve around yours?
Something to consider - if you live in a big city and there are many THS sitters, those trying to build their number of 5 
reviews as sitters may be inclined to take your sit. Having 1 indoor outdoor cat does not take a lot of effort on the sitters part, you could use sitters who are relatively new but ONLY if you feel you have the special skillset of a good video chat type meeting to decide if they are a good fit for you. If they are close enough, maybe they would be willing to do an in person meeting. You have much to think about. Best of luck.
I did, but took it for granted that you’d read the fine print before joining. An error of judgement. My apologies.