I didn’t read all the answers because I’m literally boarding a flight. But, I would do the smallest down payment that I was personally comfortable with. Get into one deal. Get your feet wet.
In order to pick market you can either go with what excites you or go with top performance metrics (see my bias here).
If beach resonants and will add some additional satisfaction and quality of life stuff then do it. It would be more like a lifestyle asset.
If you plan to self manage get a coach and pay to learn. Don’t mess around with teaching yourself. Keep the remaining cash as cash reserves for now, maybe do some forced appreciation or value add and get the property that’s in the best location with the lowest price per sq ft. Get an agent who is also an investor in the exact thing you are looking to buy who has a good performance record.
Do it for a minute and make sure it works - weeks / months / years - you’ll know. Then 10x in same market since now you have your process and team. OR you could pivot to another market but only if that will bring you personal satisfaction and you won’t be self managing. That’s my two cents!