it's not a black and white answer.

Do you typically make all adults (a couple, etc) pay to apply?

The first time I saw him, he approached me, asking me personal questions in a very rude manner, I mean obviously he knew I didn't live there (btw I'm Hispanic) And the majority of the residents are older white retires.

Typically its no Issue untIl you have to do an evictIon or when cIty fInds out.https://www.citybuildingowners.com/rules-for-new-york-city-basement-rentals/Read the article should have the details you are looking for..

If you built a triplex next door you wouldn't necessarily need to split the lot if you were looking at a build and hold scenario and you could get owner-occupied construction financing.Doing 5 or more units on the same parcel puts you into commercial loan territoryYou could however potentially split the lot and then build a four-plex next door and stay within residential loan guidelines.Construction loans in my area typically lend 60-65% loan to costYou may have enough equity in the house to be able to get that 65% financing without any cash out of pocket.If you were able to split into 10th of an acre lots you could phase the build out of 6 single family homes: BBRRBuy, Build, Refinance, RepeatGood luck!

In a traditional multifamily, everything is typically submetered , and the owner doesnt have to worry about most utilities , since the tenants are each responsible for their own.

@Tyler KastelbergHi Tyler, what is the typical cash on cash return in passive RE investment instruments like apartment buildings, commercial RE, RE Mutual Funds, REIT?

Typically, your first deal will never be a slam dunk. 

It's typically a pretty predictable 30 day process, and with a hiccup you might push to 60 days, but it makes jumping into even high-risk areas a lot less daunting.

Sounds like the granite counters question in another thread to me.Actually if the typical tenant expects it, you should probably do it to be competitive.