You have to pay reasonable/logical (whatever word they use ) interest to allow the IRS their pound of flesh. 

Typical target for most Rental arbitrage investors is $1000 NOI (net operating income  = revenue - expenses).   

In addition to posting on here, I recommend you search on your local facebook group that is specific to your target area.

Is there a target percentage I should look to bring to the table?

Any cash flow investors out there that can give their input on acceptable margins for either a rental or rent to own strategy on older mobile homes? We are seeing returns well above average.

If you want to lighten the look, just paint it a neutral color.As for the rest of the finish-out, if this mobile home is targeted at affordable housing, then you want to give the illusion of luxury without using expensive materials.

Is that the target size of most of them?

This is the target price for first-time home buyers and investors.

If you are trying to leverage a property as a house hack, then I would let my target cashflow be what qualifies a good or bad deal. 

I have an investor that will fund all my wholesaling deals for no transaction fee, but they don't finance rehabs and I lack the capital for the down payments so I have targeted a few REOs and preforeclosures that I believe I can buy that would appeal to rehab investors and a few that would be turn-key for the buyer.