Generally, the laws get more restrictive as you get more local.

In the area where I have my SFR rental, laws restricts 3 or more unrelated people from renting a property.

If you want lower your standards that’s your choice but be prepared for issues either with damage or non payment of rent and going through the process of eviction all while you’re collecting nothing and having to pay the expenses along with legal fees.

you may want to find out legally if you can send out an addendum to leases with a pet policy to all your tenants ( this way you are not discriminating) and let them know that as the owner that, that is the new policy.

If that's true it'd be mighty fine of you to not do any of the above and move on to a more legal business venture.

Remember he pays all costs/legal fees for drawing up th emortggae.You need a significant non refundable DP to cover your costs if/when he defaults.

I would make sure it is a legal bedroom in case there is an issue and you have to contact you insurance company or you are reported for substandard to the current code.

Not a big fan of including all the little fees in my calculations, legal, marketing, etc.A 2/1 in 'C' neighborhood rents for 1800 a month in Westchester? 

Long term it gets complicated and also if you have heirs to inherit it there are many restrictions . look up Kareen hall and udirect .

Either way, I would find a way to get rid of this tenant legally.