Pinball is a luxury item. It's a "want", not a "need". So you had a bad experience, and lost some money. Oh well, life is full of bad experiences.
Working on your own games is a must. If you can't do that, you need to learn. Find a local tech that works for cheap, because you're always going to have repair issues. Maybe he can show you the ropes. Everyone needs to start somewhere.
But, with all due respect, it may be time to find another hobby. Sell and cash out. Do something that's fun and less stressful. Pinball isn't for everyone. It's expensive and requires heavy maintenance.
