Well you need to determine just how in depth you wish to get into sausage making.
If you are only making a pound or two of basic sausage at a time you can get by with a cheap grinder or grinding attachment coupled with a stuffing attachment or a horn stuffer.
While these can be difficult when making large batches they will work for occasional use for small batches without breaking the bank.
If you plan on making a lot of sausage and different types on a regular basis, I would suggest that invest buy a good heavy duty grinder (at least 1/2 hp) with a wide variety of grinding plates available for it. Weston and LEM make great entry level heavy duty / commercial grinders. The important thing to remember is that make sure the grinder itself is made of stainless steel for easy clean-up and sanitation. These not only make the task easier, but they save a lot of time and frustration.
If you are making more than a few pounds of sausage, a gear driven sausage stuffer will make your life so much easier. Again make sure you get stainless for easy clean-up and sanitation. Again these save a lot of time and make the job so much easier.
You don't need the biggest and best, but practicality in selection is a must for your level of use.
Other things needed are buss pans, Large cutting board, a good set of boning knives (semi-flexible and stiff), a good utility knife, and a cut resistant glove designed for butchering. A good book like Stanley Marianski's "Home Production of Quality Meats and Sausages". This book coves not only a wide variety of sausages, but also cover curing many different meats as well. It is a combination of two different books combined into one.
Most of all make sure you read and understand about the proper use of cures in sausages/meats to avoid any illnesses from using too little or too much.
MEAT GRINDERS (links below)
Sausage Maker
LEM Products
Weston
SAUSAGE STUFFERS (links below)
Sausage Maker
LEM Products
Weston
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