I'm a Miami Realtor and have helped dozen of investors buy condos and houses for short term rental in Miami. Here's my advice:
1- Be prepared to buy in cash or start thinking like an underwriter. Lenders will want to see at least 20% down payment. Single family homes are a little more flexible. Most lenders do not like condo-hotels since they are "risky" and have a higher default rate than owner-occupied mortgages.
2- Miami is not the market to "get a fire deal". Everyone wants to be here. People are realizing they can work and live here. Miami is no longer just for vacation. Companies are moving their headquarters here. The "deal" is the property you buy today and HOLD for the next 5-10 years. Read on about new construction.
3- Have a team. You need a great team that can work together to make the deal happen. At a bare minimum you need a real estate agent that knows the market for STR, local mortgage broker, attorney, property manager, contractor and a designer.
4- Consider new construction. Right now there are less than 5 STR condo buildings in Downtown Miami. There is a wave of new construction condos that have a in-house operator and allow daily rentals. The best hedge against inflation is pre-construction projects. Buying at a fixed price today for something you will receive in 2 years.