1.  Back lit display - A small thing, but useful if you are measuring in doors in a dark room or space.  Many models, like the Disto E7300 have a small photo sensor that switches the   backlight on and off automatically.

2.  IP moisture and dust number.  A IP54 is a good number for dust and moisture protection.

3.  Working temperature range. Cold winters and hot summers are unkind to electronic tools.  Check the storage and temperature ranges for a laser distance meter before you buy.

4.  Two year warranty (minimum) - peace of mind, plain and simple.  Make sure the dealer you purchase the laser distance meter from has a good warranty policy.  The Leica distance models have the best warranty.

5.  Metal thread tripod mount.  If your measuring jobs require you to use functions like pythagoras calculations or height tracking, you need the tools steady and a tripod is really a must have   a plastic thread mount can crack.  Look for a good metal tripod thread.  Examples of this, would be Leica Disto E7400, E7500 , E7500i, D810 or S910.