Hi @ArnaudA,
This can indeed be achieved with calculation properties: Create calculation and rollup properties
I’ve explained how to solve the first two of your bullet points here: https://community.hubspot.com/t5/CRM/Create-property-that-sums-deals-over-specific-date-range/m-p/1047800/highlight/true#M151991
Your third point would be another additional custom calculation property of type boolean, for example, using an IF function to check whether one property is greater than the other and then returning true, if not return false.
Give it a try and let me know if you’re getting stuck and if so where!