@Kyle-And-Jess0 A guest can't "ding you in return" for the review you leave- reviews are blind, so your review isn't visible until it is published, and then it is too late for the other party to leave a review. The review period is over as soon as both parties have left a review, or at 14 days if only one of you has. The guest can leave a response to your review, but the response appears on the guest's review page, not yours, so future guests will never see it.
So always leave honest, factual reviews. Don't speculate as to motives or outright accuse a guest of something you can't prove. You don't want to chance having the review removed because some CS rep decided it violated review policies.
"There were a number of missing items after this guest's departure" is just a fact- you haven't said they were thieves, but it's obvious to other hosts reading it that they were. If you have camera footage of them walking out with your stuff, you can submit that to Airbnb and charge them, if you feel it's worth it.
Try to be balanced- if there was anything good to say about a guest, work that into a review, but don't wrack your brain trying to think of something positive to say if they were just all-around crappy guests.
If you find things missing, a message to a guest like, "Hi XX, after cleaning the unit, we can't seem to find___. Did you put it somewhere we may not have looked, or maybe accidentally pack it with your stuff?"
Hosts have gotten things back like that- either the guest did stash it somewhere strange, did accidentally take it, or took it on purpose, hoping it wouldn't be noticed, but when asked, did the right thing and returned it.
However, in the scenario you described, that approach would likely be useless- they obviously fully intended to make off with all of it and aren't even likely to reply to a message about it.
Do not leave things like boxes of 80 trash bags, 24 packs of toilet paper, etc, where guests can access them. Try to leave only enough of everything for the number of guests and the length of the stay. Doesn't mean you have to be chintzy- a few extra rolls of TP and few extra garbage bags is fine, just don't leave what would have lasted you for the next 3 weeks and 6 guest changeovers.
Some guests are actually clueless, and think all available consumables are for them to help themselves to, like they would take all the toiletries in a hotel room, and some are just greedy, disrespectful cheapskates who know they are stealing, but want to get their "money's worth". Easier to just remove any temptation.
As far as the extra guests go, if you have footage of them entering and not leaving all night, you can try to charge them for it, but the hassle and time might not be worth it.
I'd tend just leave a scathing review, mentioning the missing items, the extra guests seen on the last night, and the mess they left behind, and then forget about them.
(If you don't get a notice that the guests have left a review during the first 13 days of the review period, write out your review offline, then copy it and submit it 5 minutes before the 14 day deadline. By the time they get the notice that you have left a review, it will be too late for them to submit one. Although they can't see your review before it's published, guests who know they've behaved badly will often leave bad reviews, because they assume you have. But they may not review at all if you don't review until the last minute. If you do get a notice that they've reviewed before the review period is over, there is no point in waiting until the last minute)
