A conventional storage tank water heater has a life of about 10-15 years, so if your unit is in that age range, it may be worth footing the cost to replace your water heater than constantly fixing regular problems as they arise with age. However, if your water heater is only a few years old, repair may be the way to go.
As well as typical modular homes are placed on land you own. If you meant a mobile or manufactured home then anywhere between $2,000-$3,000 including all permits, set-up, even electric/ac hookups moving around 20 miles distance. This is only an approx number assuming the home is a single-wide. If the home is a double wide OR a number of pop-outs, add-ons, or sun rooms then the price will go up rapidly. Also double-wides never quite go back to the pre-move look and feel, they always seem to be a little off when reconnected.
ADT prefers to send an associate for their evaluation of your home security needs prior to installation. Most of the systems are wireless but hard coding is required with certain add-on equipment. ADT offers a basic home security package for a $99 customer installation charge plus a monitoring fee of $36.99 per month.