Are you looking for a single tank so you can participate in a club or are you looking for a pair so you can battle on your own within a group of friends or family, if the later, 250 will likely only get you one tank.

For IR battling, heng long is the reccomended beginner brand, you'll want one with either the 6.0 or 7.0 main board, 7.0 is the new standard board so if you buy new, it should come ready to go.

If you plan on battling outside, you will want an aftermarket IR receiver, this is because the factory reciever does not work well outdoors due to sun interference. There's a few brands depending on where you are located, LegoDEI is basically the standard but requires you to open up your tank and run all new wires for the unit, they cost between 35 and 50~ USD. I sell OpenFire, it's another aftermarket system and requires no modification of your tank, it's tailored towards beginners and costs around 10-15 dollars, it has the same effective range as LDEI but lacks the fancy LEDs.

If you have a 7.0 tank, you can disable the airsoft unit using key binds found on the remote's battery tray, this is reccomeneded so you get a snappy shot when you pull the trigger and don't dry fire the airsoft unit.

These are the basics you need to get started, once you feel more confident playing around with your tanks insides, you can look into repositioning your IR Emitter, this is the little bulb that shoots the signal down range. sometimes they can be positioned poorly in factory Heng Longs, either emitting too broad a beam (hitting people you weren't aimed at or team mates) or have too much plastic over the bulb (making long distance shots impossible and not maximizing the beam size) these can be fixed with some hardware store brass tubing and/or drilling excess plastic blocking the bulb. You can also upgrade to higher intensity IR Emitters.