Engage an investor-focused realtor/broker in your preferred market (this is not a residential realtor) and start 'tire kicking' the market and properties that fit your criteria.

That being said, and this is not for a sourcing homes for sale, but to source accredited investors in my line of work, the average marketing agency is looking at about $30-50/accredited investor lead setting up a call. 

Found it through a broker on the market.

This strategic flip leveraged our market expertise and efficient deal structuring to achieve a quick and profitable transaction.

The benefit to buying cash and refinancing later is that you can close on a property quickly, which works in your favor in competitive markets.

However, the property’s cost basis (what they originally paid) carries over to you, meaning if you later sell, you may owe significant capital gains tax on appreciation.Alternatively, selling the property at fair market value eliminates gift tax concerns, but your in-laws may owe capital gains tax on any profit.

@Todd Anderson totally agree on finding a mentor in the market to learn from.

I’m looking to invest out of my home state, Texas, and have narrowed it down to 3 markets.

As an aside, insurance companies are inspecting most properties one way or another in the current market. 

There's a reason that people try to buy properties off-market and that is because you can find sellers who care more about terms than maximizing returns.So start with a conversation: you already presumably have some rapport since it's your landlord and you've spoken before.