This would be my 3rd rental property by the way.

I'd like to make some rental friendly upgrades and upgrades In general to my 1910 home but don't know where to start. 

Other reasons for denial involve other risk factors, such as, 1. rental history and prior landlord verification 2. credit score3. employment history and verification4. income v. rent ratioetc. 

I used to live in northern Illinois, so close to Wisconsin - there are several smaller towns around lakes that would be good for short term rentals. 

If property insurance, it should already be covered by your insurance company and you can ask them to add loss of rental coverage.

This book got me off the sidelines and in the game: Build a Rental Property Empire by Mark Ferguson and this book elevated my landlording methods: Managing Rental Properties by Heather & Brandon Turner~ Lindsey

Currently the rental income im getting is covering 30% of the monthly motgage payment so i was wondering is that was a good ratio to justify the house hack.

if you're hiring a PM - let them handle it for youor, go to a REIA meeting, make friends with a realtor, and ask them to run a CMA for youor - look for other active rentals on a whole bunch of different sites and see what others are listed for

I'm not sure where to start with private money or hard money lending when it comes to covering rehab costs on a rental property that we already own.

You can track materials used to fill in your JIT processes or whatever.With a vacation rental, it is always different.