How to proceed with non-paying tenant

[Daniel Suarez]

I have a tenant who's always paying late, but this month he's already behind December and January. He's a good tenant, keeps the house clean, does not ask for many things and does some repairs himself. 

He says he will have December and January both by the 15th (he says he's working extra hours) Now, my plan is this; if he doesn't pay most of it for both months by the 15th, I will get together with him and offer cash for keys (trying to avoid eviction for many reasons) My question is, where do people actually meet with tenants to discuss this thing? He owes 2 months of rent, we you offer the cash, do you let those unpaid months go and just keep the deposit?, if he doesn't show up for the meeting I'll evict right away.

Also, he's a police officer, and although he's never even suggested using that as leverage for not paying rent or anything, I'm a little worried because well, he has a gun.

Thanks in advance.