The two points that would matter most to anyone running property operations are the partial payments and the tax-per-unit rules. Tenants rarely pay exactly one instalment, so showing how a payment is split across instalments before it is confirmed is the difference between a clean ledger and weeks of reconciliation. The same goes for tax: if the system doesn't know the unit type first, the invoice will be wrong no matter how good the rest of the flow looks. I also appreciated the honest note that Arabic-first is an architectural decision, not a translation pass — that is exactly the kind of thing that is cheap to do early and painful to retrofit.