I realize that you feel this is an unreasonable increase but it is a necessity in order for this to continue being what it is.

Since it is a seller-financed note, I would suspect that you can draw it any way you want as long as it is not unreasonable from the buyer's perspective.I noticed that some people have mentioned the high cost of a foreclosure.

If your neighbor is unreasonable on his asks, you have the option to move yourself and expand elsewhere nearby.  

We unfortunately had to let go of one of our PMs due to unreasonable quotes and the issues they were quoting for weren't even problems to begin with.

He is just ungrateful and unreasonable.

Therefore, it would not be unreasonable to compare a duplex with an ADU to a triplex for this approach.

Its not unreasonable to expect a prospective buyer to be unaware as well.4. 

I don't think that is an unreasonable amount, especially since you would be inheriting all the future risk.

In this case there would be early discharge penalties due and it would not be unreasonable for your partner to expect you to shoulder these fees since you are forcing the situation.  

Your landlord is either being unreasonably inflexible or reasonably sees greater risk in renting only to your roommate.