I have student rentals, summer is not a problem for me, the lease is 51 weeks. I leave one week for turn over. This is typical for my area, 12 month lease, they can sub-let in summer if they want to . You are better off renting the whole house to a group, where all are equally responsible for the rent and any damages, let peer pressure work for you. Rather than individual leases for each one. They can work out for themselves what each room is worth, and who pays what for rent, utilities, etc. I don't care or need to be involved in how they choose to divide up the expenses.
Obviously with COVID who knows when schools will get back to normal, so I wouldn't buy anything for the foreseeable future.
Pro's, almost no vacancy if it's a good property, proximity to campus being the most important. They always pay, or their parents do. I don't know where the money comes from, as long as it's paid I don't care.
I haven't had many problems in terms of damages, you have to accept that it's going to happen and don't get too upset when it does. There will be more damage than if it's a family, but mostly it's small stuff. The extra rent I can charge more than makes up for it. The biggest issue is these kids don't know how to fix ANYTHING themselves. "my towel holder fell off the wall, please fix it" "the light in this room stopped working" for little stuff like that we (my PM) try to coach them though it (like how to replace a light bulb) or wait until there are 4-5 things needing to be fixed then send someone over. I created a little book with instructions on simple stuff, like how to shut the water off to the toilet if it starts to overflow, stuff you can, and can't put in the toilet. How to reset a breaker if it trips.
Make sure in your market some developer isn't planning an 800 unit student apartment building. I think smaller schools are actually better, large developers won't move into those markets.
Make sure you know your market, what the norms are, what the schedule is. For example in my market, people start advertising in Oct-Nov for the following Fall. I had a signed lease in Nov 2019, for June 2020 move in. If you buy in April-May for example, you may have missed the rent up window for the upcoming school year.
Lots of great info here:
https://www.biggerpockets.com/forums/52/topics/491641-nearing-1-000-college-student-tenants-heres-what-ive-learned