For landlord : Giving free rent / discounts

As a landlord, I am considering the option of giving temporary rental discounts for a new tenant (instead of a lower monthly rent) and wish to know if there is any legal risk, and how to draft the clause (same agreement or separate addendum) Context =========== Since Covid many big cities saw exodus of tenants, and I've seen this to be a common way for owners (in other countries, eg USA) to drastically cut expense for tenant without lowering the official rental valuation and without getting caught up in rent control act. E.g. 3 months free on 12 month lease. Although it's effective 25% lower rent for one year, but it's very different in nature, since it is temporary, and when tenancy is renewed, the discounts do not renew automatically. My Proposal (as landlord) ====================== Monthly rent: 21k per month, 12 month lease, 5% increment on every renewal (this is standard agreement) Rent discount: Zero rent for 3rd, 5th, 7th, 9th months. So tenant in total pays for 8 months in 1st year. No further discount after that (in case lease is renewed) Both tenant (the prospective one) and landlord (me) has agreed to this. My queries ============== [1] Is there any legal risk or implication of making this offer as landlord ? [2] What is the best way to draft it - eg in original lease agreement, or separate addendum [3] I would like to keep the option of offering a smaller discount on 2nd lease year, totally at my discretion, but not commit anything now. Do we (tenant and landlord) need a new agreement / addendum, or a email communication confirming our mutual consent is ok. I have drafted the details of the variable rent schedule, conditions (e.g. non-recurring, not applicable if tenant previously defaulted), and how the pro-rated rent would be calculated if the tenant quits in the middle. I would like to get it executed as part of standard lease agreement.