1031 and FAFSA plus WWYD with investments

[Alys Brown]

Experienced renovator but newbie investor + single mom with 2 kids, 9th and 4th grades. I own real estate I've renovated and all are paid off in full: 

#1) primary home until mid-last year (approx $1M), market in going up and in fast-growing top 20 city and close to center city. My plan was to rent it (approx $4200/month) for 2-3 year, use the money to make updates and capture further growth, then sell and put into 1031 since I'm single and will have closer to $400K appreciation. We moved to a better school district; I'm renting now until I can find a house to renovate. It will be much cheaper than this house. I've learned my lesson about larger and expensive houses - more costly to maintain and harder to rent out. 

#2) Former home in another state, worth approx $275K, currently rented for $1500/month. In a growing beach resort. No chance of flooding. I can rent yearly but not AirB&B. I had a lot of interest when I rented it out last summer and have a great tenant. I rented it out several years ago - I can keep it rented, although quality can be an issue at the beach.

#3) Land in same place as #2. Was going to build when I moved. Approx value is $300K. It's in a desirable neighborhood in a growing beach resort....but not so close to water that it will be flooded. Land is worth more than building and then selling.

Also investing in a new business idea I have. I own another business that has seen a steady decline so time for something new.

Any suggestions are welcome re:  

1) Maximizing investment potential. I find it hard to sell once I buy! And I like to own things outright - easier to sleep at night, since I'm the only income producer, but I know not always the best investment idea. Also, almost all my net worth is in real estate. 

2) My older kid wants to be an orthodontist and has many years of schooling ahead, so if I can make any changes now knowing FAFSA is coming in 1-2 years, this is the time. 

Thanks for reading this long post and especially any recos!