I strongly recommend NOT using this product for any multi property environments since the derived "protel Air Central" seems to be a newly built product rather than an add-on to protel Air, therefore has more bugs but fewer functionalities. Much the same applies to protel Air, some functionalities known from the previous "protel cloud center" were just not built into it. If you take a close look you will discover a multitude of apparent functionalities, some will be shown to you before contracting to prove that protel Air really does all the work for you, but once implemented you will be surprised to experience that input fields, buttons, filters are often just a facade - obviously like an advertisement for some really useful function intended to be implemented later. I am using the system since early 2023 and was informed then of many updates and fixes to come, none of which have been delivered by the time of writing this review End of August, so it might be prudent not to expect those buttons to start doing their job before 2025, which is a shame since the developers seem to have been full of good intentions. F.ex., there was an "alerts" button which has only recently been removed since it stopped working after the pandemic. I was informed that it was "only intended to remind staff to ask for proof of vaccination but kept on for later use as normal alert function" (familiar from Oracle and others), then some day an update notice said the button was removed because it did not have any functionality... Also disrecommended if your staff needs constant guidance and supervision and/or your guests have a variety of individual needs, since you can either set few simple rules which protel Air then upholds to the bitter end (for example, a guest on a 3-nights-special cannot leave early. Just cannot. Pay the due CXL fees and depart? No, you have a 3-nights-special, sorry Sir, please to come to check out tomorrow. You go straight to hospital? That is totally ok as long as you sleep here for the night and come to check out tomorrow) and therefore allow staff the absolute minimum chance to commit any foolery, or you can set a variety of options from which your staff will be sure to pick the wrong one at the worst possible time (protel is not to be blamed for the scarcity of good staff, however it does nothing to help you work with what you have to work with). Totally disrecommended if you use and RM or BI software since protel's "one size fits all" interface does just not support intelligence - "no Sir, a room is either booked or not booked. Options, allotments, crew/group/corporate contracts and all this alien stuff may be well for foreigners but certainly will not be accepted here". And if you still do not believe me, try setting up rates for multiple room types with seasonal basic rates, weekend supplements, length of stay/advance purchase discounts and different levels by distribution channel - and then go and yield those rates. Daily, if you dare. Oh, and the absolute final straw: Do not use this product if you need product support. The help database shows as much in-depth product knowledge as the majority of their support agents, and even their few dedicated and resourceful agents are thwarted by... yes, protel's iron rules! Sorry Sir, restricted area, software developers only. I have not been able to determine if they have 1 developer only, or 2 developers both of whom are working part time, but most likely they have 3 on permanent sick leave and a night watchman to tend the shop. I will not get into the groups or allotments modules, split invoices, shared rooms or any of those "irregularities" because this review has over 600 words already.