If it holds up under these conditions, you've got a solid investment—better safe than sorry!

It is also great to change small but specific terms and conditions due to it not being just one tenant anymore.

This includes cap ex, repairs (will a renter leave the property in the same condition you hand it off in?

“it is VERY hard to screw up when buying i.e. a duplex in good condition in a desirable neighborhood and either self-manages or hire a quality PM to manage.”excellent point 

"I'm at the point where I've gotten out THE lease and it doesn't have anything about locksmith, however the maintenance, repairs section states, " All normal repairs necessary to maintain premises in a tenantable condition shall be done by or under the direction of the landlord, and at the Landlord's expense, except those caused by negligence or acts of the Tenant, which repairs shall be made at the sole coast of the Tenant. 

You can make minor adjustments based on the type of appliances (dishwasher, clothes washer and dryer, air conditioning, etc.) and the size of the rental.

Low or no down, seller financing and low or no interest with a balloon payment later is the holy grail (location, building condition, market also matter but it sounds like you have all that).

So having a borrower sign a deed in lieu AS A CONDITION FOR MAKIMG A LOAN is not going to stand legal challenge.  

I have little confidence in turnkey providers, deals are already hard to come by, if they take another 20% cut before.. much better to buy a property from an owner that is in good condition.

For this deal to work under those conditions, the purchase price would need to be closer to $179k.With your original assumptions 249k, the deal is marginally acceptable but not great, given the negative cash flow in the early years.