Small Engines (Lawn Mowers, etc.): Briggs valve repair tools, neway valve seat cutter, briggs stratton

Question
Paul,

I have started a small engine repair shop just as  a side business. I  particularly  work on push mowers and tractors. I am still assembly my tool inventory and I wonder if I should invest the money into the following tools. Briggs & Stratton valve seat puller kit #19138 , 1/4" and 5/16" valve guide repair kit, also a Neway valve seat cutter kit. These items are quite pricey and honestly how often will they be used , especially since I am not doing this as a full time business. also, there is no machine shop close to me that will do valve guides and seats. Thanks Paul, I enjoy reading your answers.

Answer
I have owned all the above tools for many 20+ years.  The only one I have ever used is the Neway.  

As a new small engine repair tech I can tell you if you need the other tools you are working on an engine that you can't make money on.

Remember, a small engine shop is there for 1 thing, making money.