Cat Climbing Tree (Granton EH5)

We recently adopted an 8 year old cat from a carer after her previous owner passed away. She's a shy little lady but can tell she's got a lot of energy to burn off. Looking for a cat tree, im relatively good condition, so she can look out the windows (our windowsills are too shallow for her to sit.) This would be really appreciated as we want to give her the best rest of her life but we are unable to financially do it due to ill health.