I just checked whether there were any post about home exchanging here, and I found no one, so I decided to share my point of view on homeexchanging. Probably most of you already know a lot, so I advance I am most likely telling nothing new to you. My experience is with just one platform, so some of the things I say here could not apply to all of them.
I began home exchanging in 2019, and since then I have (happily) participated in 57 (half) exchanges.
It is usually believed that home exchanges must be symmetric: I go to your house and you come to mine. However, this does not need to be this way, but it can be this way. You can set whether you want it this way or not. For me, it is highly unlikely that my interests perfectly fit someone else's for a reciprocal exchange. The other option is to let your place for some "coins" and use this coins to go to some other's place. This needs not be in the same period of time.
Home exchanging can also work for the entire household or just for a room while you as host / your host stay at home. I have two different ads, one with the apartment and one with the guest room, and I offer one or the other depending on my availability.
Different types of houses / apartments have different "coin" value, depending on size, number of people that can stay, location and facilities. For reciprocal exchanges you can choose either using the "coin" value and pay / receive the difference or consider you want reciprocal exchanges not using the "coin" system. There is some flexibility deciding the "coins" your home costs, with an upper bound decided by the platform.
There is an anual fee to the platform. This comes with the upkeeping of the web plus some guarantees in case some exchange goes wrong. Some money is supposed to be put on hold on the guest's credit card in case there is some damage to the host's property, but I have never had the need to demand anything (someone broke a glass, but I call this life, not damage, and I once broke a small piece of the kitchen and I managed to buy a replacement for it, altough they received it 5 days later).
Some houses / apartment charge for clean up after the stay, some do not. It's up to you whether you charge or not and whether you choose apartments which charge or not.
There is a (for me pretty honest) point system for hosts and guests. 5 stars are not guaranteed!!! You can choose the houses you apply to seeing this, and you can be accepted or denied the request depending on this (and many other reasons).
You can publish which dates you have your place available and fliter by dates for available houses / rooms.
So far so good....
Caveats.
The "central bank" issuing the "coins" can print as much "money" as they want. I do not like it, but I do not see how they could avoid this power. I do see how they could not use this power as they do: they give free "coins" if you referee new members and for these new members. They also give free "coins" for automated renewals and, sometimes, for stupid actions such as requesting stays even if you are not intending to make an exchange (which fostered just waste of time for people receiving almost void requests). It seems they keep inflation pretty well, at least as far as I can see.
This availability to print "money" is what makes homeexchange be able to offer you an alternative in case someone cancels the place you are supposed to go: they immediately look for an alternative, offering extra "coins" to the potential new hosts. I am not sure whether there are also similar protections in case the place you go to is baaaaaaad, since I have never had such an issue.
Many people do not keep their calendars updated, which is a bit frustrating sometimes. Some do not even write back, and you do not know how long you should wait for an answer. Some of these things led to some (many) people sending many requests (I do not know how many, 10 perhaps? 20? 5?) and finally choosing at their best interest among those who accepted. For me this has not been good, since sometimes I accept someone's request and deny another, but the one I accepted then says they got another place... I think this attitudes should be handled, perhaps diminishing just a few "coins" if you ask for a place, you are accepted, but you finally decline. Imagine sending 10 emails to 10 restaurants booking a table, and the next day cancelling 9 of them.
At the beginning you do not have enough "coins", and you cannot benefit of it until you have earned some. You can try synchronizing welcoming someone (you get the points once you accept people, you do not need to wait for them to arrive to receive the points) and then look for a place for you. However, you do not still have any reputation, so it can be difficult for you to find what you want. For me it was very easy, because I travel for work twice or thrice a year and I had my place available, and at that time there was no need to pay the platform fee just for receiving guests, so I spent a year earning many points and some reputation as a host before being a gues. However, now you must pay the fee also for hosting someone, so it is not that easy.
For me, it has been a great way of having holidays. I think that empty houses (even for just a few weeks) are resources somehow "wasted", I have no privacy issues (but lately I have put a lock in my room when I go away and I just offer the rest of my apartment, so I am even more confident) and I have not had a single bad experience. Out of 57, I had a 3* one and a 4* one, rest 5* (but I am not demanding, as long as the information provided is accurate; so a noisy place which adverts as noisy can get a 5* for me).
Some years ago people were kinder, we used to leave some small present, less places charged for clean up... but anyway it keeps being good for me. Not everything is wonderful, but I think it is a good choice.
And, of course, this a very good way to skip airbnb and all these predatory companies and predatory landlords.
If you have any questions, I am happy to answer (private or public, except the particular platform on public).