, but I want to be sure we are both protected from the other's potential partnership liabilities, whether intentional or not. 

I've seen a lot of similar things.Obviously the intent is this allows greater access for people with disabilities, for example a wheel chair. 

All initial intentions were to build and hold for long term investment.

It could be a short term investment with the intent of increasing NOI and refinancing to pay the investors back, or it could be a long term hold.

If they buy the property with the intent to fix it up and re-sell for profit the IRS views it exactly like inventory for any business. 

@Mike WessellLand/real estate is considered inventory to dealers.Inventory does not qualify for installment sales.You would have to change your intent to get the benefits of installment sales/1031.

I told him to let me think about it and I'd get back with him soon.I just worry that if I ever decide to sell the house that a walk-in tub would negatively affect the re-sell value, especially given that this is essentially a starter type home...My initial reaction is no, but then I think that if they want to make this change and pay for the modification, they have no intention of leaving and I would have a very long term, dependable tenant.Could I stipulate that they can change it out but if they decide to leave they have to swap it out for a one piece shower/tub combo that I originally had?

Hopefully, if you are being pitched by someone exaggerating their experience or who has self serving intentions, you will be able to figure that out before you get financially connected to them.

It is about intent. 

I would like to remove some of the equity in the home to use in another investment (I have 2 other rental properties at this point that I paid cash for and am rehabbing with the intent of refinancing.