I know this is an older thread but, maybe someone will look that can use this information today. I've been buying, selling, servicing and installing auto shop equipment for well over 20 years. Buying a used lift is a smart move. When doing so, it would be wise to send someone like myself to inspect the lift before you purchase it. If you choose to do the inspection yourself, there are some things you should look for. There's no need to replace the cables unless the cables are frayed. If they're not visually frayed, they're fine. Inspect the hydraulic hoses. If you see signs of a leak or if the hoses are rotted and cracking, replace them. If they're not cracking or leaking, they are fine. Smell the hydraulic fluid that's in the reservoir. If it smells burned, it indicates lack of maintenance or it may say that your pump is struggling and will eventually go out. Check the lock mechanism. Be sure that none of the pawls or bent or damaged so that they don't make good contact with the lock ladder. If you can't see visible damage to any of the lock system, it is fine. If the lift has an overhead mounted cylinder, consider that you will need some type of equipment when you do your installation. If you don't own equipment, you may want to check on the cost of a rental and figure that into your budget. If you're planning on hiring someone to install the lift, to install a 12,000 lb four post, I would charge $1,050. That price does not include the electrical work. That price does not include the new anchor bolts if it's a pre-owned lift. That price does not include the cost of the equipment rental. Chances are you will need a forklift even if The cylinder is mounted underneath the runway. A 12,000 lb lift has very heavy components. Without experience, it would be very easy to hurt oneself trying to handle some of the lift parts. All in all, the old saying stands true, if it ain't broke don't fix it. You could run into a ton of money replacing cables, hoses or any other components without it being necessary.
