Very cheap tactile switches

Parts Questions
1

I’d like to buy very cheap switches for my test setups only …

  1. Where to get the cheapest ones?

  2. Can I run into problems with cheap switches (specially when multiplexing)?

Thanks and greetings

Roger

2

I bought a lot of tactile switch on ebay, always cheap… But they need caps (and this is a problem for me for about one year now!!!).