Key Copying Questions

[Rob888]

My car is a 2010 Yaris 3 door hatchback. It has an immobilizer.

I have one master key and one valet key.

I want a third key so I can put the master key in storage so I don't lose it and only use it to make key copies.

The only Yaris keys that can be programmed without software are for the 2007-2008 model Yaris, correct?

From what I have read, using software like Toyota Techstream or whatever to program keys risks screwing up the car's computer, correct?

Getting a valet key copied is a lot cheaper than getting a master key copied. So can I use a valet key with a separate remote fob for the door locks instead of a master key with a remote fob either attached or separate? My glove box does not have a lock on it, and I never open the rear hatchback door with a key. I only use the key to start the car and the remote to open and close the door locks

Thanks for any replies.