I have a couple of small properties that I would like to lease to startups and tech companies.
By Startups, do you mean "I have an idea" or "we have seed funding", or "we're profitable"?
In any case, this is going to depend on where the properties are located.
"I have and idea" - research co-working spaces, and don't expect the income to pay the mortgage any time soon. Running such a space is a full time job for one or several people.
"We have seed funding" - research co-working spaces that have additional space for companies to move into.
"We're profitable" - talk to some local companies that fit this description and get direct feedback.