100,000 in cash means you can get another 300,000 in loans (give you have a good credit score).
Business ideas depends on your circumstances and preferences. If you are working daytime you would need something in evenings, if you are not working at all you would need a different kind of business.
with this investment I would think of franchising a restaurant/cafe (you can easily get Boston Pizza, Pizza Pizza or such franchises with this much investment). Another I know of is like dollar store (A buck or Two) I can connect you with them.
You can also have Mr Lube or Midas workshop franchises if you are in that field.
Moreover, last but not least you can just lend it to lenders who further lend it and earn around 2% on your 100,000 until you find something.