We already covered the safety aspects of table saws in this post.

Table saws come in a few common configurations, specifically benchtop/jobsite, contractor, and cabinet saws.
The Craftsman 113 came in contractor and cabinet (until 1966?) configurations with contractor saws being the most common. It's a very heavy contractor saw. If I had to guess, somewhere between 200-300 lbs. I'm a fairly good sized guy and I can move it by myself with a dolly; but just barely. You'll need at least one other person to help you load it in a truck or up/down stairs.

Good quality table saws also have a milled cast iron top, which is a perfectly flat surface unlike stamped steel. An induction motor with belt or direct drive is preferable to a brushed motor for lower noise, lower maintenance, more power, and better reliability. The Craftsman 113 meets these criteria. Belt drive saws are preferable due to their power, reliability, and ease of maintenance.
The 113 also has a cable drive variety which has a reputation for being problematic and should be avoided.

The older models made by King-Seeley came with an 8 in. or 10 in. blade. 10 in. blades are the standard for table saws and a 10 in. saw is preferable for obvious reasons, although you can still find 8 in. bench top saws.

Don't pay any attention to the "HP" rating stamped on the side of saw (or most power tools for that matter). My Craftsman 113 advertises "3HP" which is theoretically impossible, even at the highest efficiency, on a 20 amp/120 volt circuit. It's probably more like 1.5 HP.

Look for a saw that has minimal rust and no pitting. The rip fence that activates the clamp by twisting the handle is OK. The fence with a lever action clamp is garbage and probably wouldn't stay straight if you bolted it to the table. Don't let that discourage you from buying a saw though as the 113 can accommodate fence upgrades.

Be sure to test the blade height and bevel mechanisms. It's not uncommon for the bevel gear to be stripped (by previous owners who don't properly lubricate their saw)

A new comparable contractor saw easily costs over $2,000. You can expect to pay around $200 for a Craftsman 113 in reasonably good condition. Even if it needs a few upgrades or some elbow grease, you'll have gotten a fantastic tool for the price.