These camera's use battery that last almost 2 weeks and take tmobile SIM card pre paid .

If the house is too far, consider the Blink battery operated ones or even hunting cameras that take freeze frames.

Replacing a 15-year old unit is the same as feeling you need to buy a brand new car because the car needs something as inexpensive as a battery for $200, or a transmission for $1500 when all the other parts are in excellent commission and the car has low miles.I am frugal and thoughtful when it comes to buying big ticket items.

I am looking to sell a condo in battery park, Manhattan but have to option to hold off the sale by a year or two in case it is not a good time to sell.

But what about battery life, reliability, compatibility, etc..  

You won't be able to monitor anything, so nobody will bother you for information.They are capable of being strapped to something with anti-theft straps or in secure boxes, but you still run the risk of someone stealing it, not replacing batteries, or other issues.The best solution is to hand it to a PM or sell and move your money to a safer market.

OTOH, you can also see those trends illustrated in those charts that show the prices of appliances, batteries, etc going down because we traded the viability of our own manufacturing and domestic blue collar work force for cheaper stuff.

The locks are also radio frequency, which means the batteries only need to be replaced every 1-2 years. 

In those cases, you have to include utilities in the rent or pass the cost on to them each month.Tenants also take responsibility for ordinary landscaping, replacing light bulbs or smoke detector batteries, hauling off trash, and other responsibilities of an ordinary occupant. 

The CE shop had a good test prep module