I will also insist on seeing every unit.

If it is about checks you can insist on one.

Insist they call you for every single thing and use your maintenance guy.  

So there is this tenant everything was ok till now but lease expires end of this month they have not pay rent for this month and insist the deposit is used for that , the problem is the deposit is there for security when they move out and they still have to pay for this month and get refund on the deposit when they move out minus bills and damages .First time handling this kind of situations , any experience sharing would help

Comment: If so, then it didn't matter what the sellers wanted to do and you should have insisted the Contract be cancelled.

I’ve seen drawings from my architect where 2bd can be fit into a sub-500 square feet plan (at the insistence of his client) and was approved, but there was almost no living room to speak of or the bedrooms were tiny to the point of impractical.

@Joe Splitrock  @Anthony Wick  valiant efforts, gentlemen, but people insist on transferring their own issues onto this post and meandering off the friggin' cliff.LOL...many people on this thread are entirely confused with the colloquial definition of discrimination (which is getting LOTS of use these days on social media) and the legal definition as it relates to housing. 

If a landlord insisted on me taking a drug test before renting to me I'd stop and wonder what kind of people were living in that building in the first place.  

@Jourdain FrancineAre you insistent that your help works at a loss?

I suggest owners insist on tenants using surge protectors plugged in to protect their appliances and devices as well as the property in case this ever happens.