If you're looking to add a little bit of height to your Jeep, a 3 inch lift is a great option. This size lift will give you enough clearance to add larger tires and make some modest changes to your suspension without making too many drastic changes to the overall look and feel of your Jeep.
In terms of cost, a 3 inch lift kit for a Jeep will run you anywhere from $500 to $1000, depending on the quality of the components and whether or not you need new shocks. If you're handy with tools and have some basic mechanical knowledge, you can probably install the lift kit yourself which will save you some money. However, if you're not confident in your abilities, it's best to leave it to the professionals.
Overall, a 3 inch lift is a great way to add some extra height and clearance to your Jeep without breaking the bank.