Under this rule, if you spend at least 100 hours on the property and no one else exceeds your time spent, you can qualify as materially participating.

Why hasn't your property manager already answered this question?

To be successful in Miami, you would need to have some serious capital to compete with the groundswell of experienced investors and developers.

The tenant wants to stay another 2 years.My other adult properties have often had long-term tenants.

While it might feel like an extra charge to tenants, these packages often provide value that indirectly benefits the property owner as well—like reduced maintenance calls or ensuring the property is better protected.In my experience managing a large portfolio of properties, these fees are becoming more common due to the thin margins in property management.

For several reasons (property taxes, politics), I would prefer to begin real estate investing somewhere other than locally. 

The government of Costa Rica has a policy to limit development and doesn't invest much in infrastructure to bring tourism.

When you work at a large corporation (national or global) you learn a lot in your role, but also by osmosis, just by observing other people and seeing how projects are developed, business is done etc.

How should I phrase my interest in the property to avoid coming across as pushy or insensitive?

I know a common practice (at least for syndications), is to create a separate LLC for the property and then raise capital once the deal is already under contract.