If you've got a little space, you can squeeze a free-standing climbing wall into your home even if you're a renter. You can spend as little as $40-$150 on lumber and hardware depending on how big your wall gets. A single panel climbing wall is cheapest. Holds are extra.

My wall, shown here, fits in my garage (I park outside). It is a little over 8' high and uses about 10'x7' of floor space. It is tiltable and also has an adjustable crack that goes from tips to chimney size. --Karl

WARNING: CLIMBING IS INHERENTLY DANGEROUS. THE OPINIONS AND DESIGNS PRESENTED HERE ARE MY OWN AND DO NOT CONSTITUTE A RECOMMENDATION OF OR ENDORSEMENT FOR ANY PARTICULAR OR GENERAL USE. IF YOU CHOOSE TO USE ANY DEVICE OR PROCEDURE PRESENTED HERE, YOU DO SO AT YOUR OWN RISK.