Issues with payment are the worst! Glad it worked out for four years, but I know how big a hassle it can be to do this dance every month.
Venmo is super convenient, but it’s not awesome for rent payments. I wrote a blog on the issues with Venmo, Zelle, and other similar payment apps.
TurboTenant’s rent collection features are built to avoid a lot of the headaches you’re describing. You can set due dates, automated late fees, and your tenant can automate their payments so no one has to rely on their memory each month. Better yet, we send out rent receipts so you both know the rent was paid!
I would follow the terms of the lease. I would charge the late fees and demand payment. I use turbo tenant and I do not allow partial payments. I would also send him a written notice reminding of the due date and letting him know payment will be due along with late charges to prevent further actions.