Buying the charging station is only part of the cost, however. You'll need a qualified electrician to wire things up, too. Some locales require permits and inspections.
An exception is if your garage already has a dedicated 240-volt plug receptacle of the proper type installed. That would let you buy a portable EVSE, hang it on the wall and plug it in yourself.
For both hard-wired and plug-in Level 2 EVSEs, you'll need to install the properly sized circuit breaker in the fuse box and run wiring inside conduit from the box to the EVSE's location.
Then you either connect the EVSE directly or, for plug-in models, install the proper receptacle so the EVSE can be plugged in. The EVSE's specifications sheet will tell you which type of plug it has. Most are either NEMA 6-50, the type used for welding equipment and for most 240-volt garage outlets, or a NEMA 10-30 or NEMA 14-30, both used for residential clothes dryers. All are pictured in this online NEMA reference chart. NEMA is the acronym for National Electrical Manufacturers Association, which sets standards for all sorts of electrical equipment.
Costs will vary by prevailing fees for electrical work, by the amount of work that needs to be done and the cost of any necessary permits.
If the best place for your EVSE is on the interior garage wall directly behind the exterior-mounted fuse panel, there will be very little wire to run and the cost could be just a few hundred dollars.
If the electrician has to run wire through the wall and then 20 feet away to the EVSE location, wrapping the conduit around a corner or two along the way, the cost could be hundreds more.
And if your house is an older one and simply doesn't have a big enough fuse box and you have to upgrade your electrical service, you're typically talking well in excess of $2,000.