Basically 90 days if you want to make a profit.

I understand that the most basic formula is ARV - purchase price - rehab = profit. 

What you're looking for is perfect for a homeowner or someone that wants to live there, but all those extra amenities (doorman, etc) are too costly for you to make any profit. 

You likely aren't marketing in the olympics, but building a strong social media platform only helps keep your property full and more demand means higher nightly rates means more profitable.

Reminder that the mom-n-pop restaurant where the mom and the pop each work 70 hours a week, and at the end of the day the net profit they pay themselves from is $80k in total.

A generation using wayfair, ikea and on demand stuff has less and less interest in DIY events, certainly not at anything resembling a profitable rate. 

The rental profits from your own property will be schedule E (lower tax), the profits from your property management company will be schedule C (higher tax).

Profitable or a loss?

One of the things to remember in owning mobile home parks is you are not only building a business to draw profits from on a monthly basis but you are also building a business that you can sell for a profit down the road. 

Sharing the profit is better than no profit at all.