These marketing techniques included bright attractive ads, giveaways at concerts and festivals, flavors, and even going so far as giving presentations...in high schools.

A good PMC screens for and attracts the right tenants, for a much lower price. 

Do any of you experienced investors/landlords/property managers have effective strategies you use to make a unit more attractive?

I once downloaded and analyzed Zillow data to find markets with attractive cap rates...

But now there is an ecosystem of lending and staking that definitely can generate yield, @Alexander Szikla, which will make it a more attractive investment for long term allocation. 

The others category of investors who succeed are those who identify real estate that can emerge from C/D neighborhood status and use the voucher recipient tenants as the lesser of two evils until the neighborhood can attract better quality tenants.

Are photos attractive?

But figuring out your strategy whether its LTR, MTR, or STR I would focus on proximity to the university and other attractions of Waco, as they say... location, location, location, it's still very true. 

Can I by way of my experience, knowledge, and capital attract OPM2.

I have seen, and used myself in situations I financed, the following scenario which can sometimes be used to “finance” a particularly attractive property especially where the purchase price is being executed significantly lower than appraised value.