Mat in the event you get another tardy tenant in the future, it does happen even when properly screening, the LTB has a excellent tenant teaching tool that I have found to be very effective. The first time a tenant pays late tell them you have financial obligations and that if it ever happens again you will be filing a L9. I like to also tell them any reason they have for paying late is there personal business and I am not interested in hearing it.
Then if it does happen again on the second of the month go directly to a Service Ontario office and file the L9. At that point it will be too late for the tenant and it will cost them an additional $170 on top of the rent they owe. The $170 is the filing fee you pay to file the L9 and the Adjudicator will always order the tenant to reimburse you along with paying all rent owed. This process may stall your receiving of the rent owed but from my experience I have never had a tenant pay late a second time. Also if they want to pay the rent prior to the hearing they still have to pay you the $170.
Some landlords may say this will your cause ill will between you and your tenant but the fact is that happened the second there rent was late. Tenants that pay late are not worth having as tenants and should be treated accordingly in my opinion. They pay on time every time or they pay me more later. NSFs are treated the same way-- L9 plus a $20 admin fee and bank charges.
I have had tenants pay the rent but refuse to pay the $170 resulting in a board hearing where they are ordered to pay me my $170. It can be time consuming but teaching people to be good tenants is worth the inconvenience of one visit to the LTB.
I strongly advise against ever filing a N8 simply for late payment as all that will accomplish is allow your tenant to vacate before 14 days pass and they will not owe you any rent. In addition if they do stay and you end up at a hearing your application will be denied and you will have wasted the $170 filing fee. The tenant simply is ordered to pay the rent owing or be evicted. This is how professional tenants live rent free for months on end. Don't play the N8 card unless you are very serious about evicting and your tenant has at the very least killed another tenant. Anything less than that and you will not win an eviction in Ontario..