The range is contingent on how much investors invest.  

We are seeing multiple offers in almost every price range again this year.

Every investor seems to have unique needs....so some want certain price range, certain area, certain type, single vs multi, dump vs pristine, cash flow vs appreciation, and 100 other variables.   

I am in south Florida, duplex are ranging from roughly 300-500k+ depending on the area.

Which I know is a hugeeee range and I am getting a little lost trying to focus it!

After getting several estimates of gross revenue from resorts within our price range, it seems like after all expenses (hoa, mortgage, management, etc.), we would be close to breaking even on most deals.  

They range from 10k-50k and are primarily located in residential areas surrounded by townhomes.

If you subject property is 1500 sf, you need to find comps in the 1350-1650 range (+- 10%, which can also be +- 20% depending on market and circumstances), adjusting for condition, location, amenities, DOM (days on market) is all the art portion.

In terms of rehabbing the property, the workflow can range from throwing a coat of paint on a wall or two, to an entire gut of the mechanicals, windows, siding, and flooring.

There are a few ways to go about it:Find a house in your price range with as many rooms as possible and rent out all the roomsRepeat option one but find a house that could be converted into two units - you occupy one unit and rent out the other unitIf you can find a house to convert into two units, you might want to look into the short-term rental rules in your area to increase your cashflow even more :)