It's hard to make a judgement based on the very limited info you gave us. If the 10+1 price was disclosed at the outset, I'd say it was unusual but not necessarily wrong. Points typically rent for $10, but you often see $10.50, 11, 12, so the price itself is not out of line.
If the person originally advertised $10, but then told you 10 + 1 when they found out you were making arrangements last minute (which means much more risk for them), I could possibly understand that. Many savvy renters wouldn't rent at all under those circumstances.
If they advertised $10, got your info, made the ressie, and then came back and said,"Oh by the way...did I mention the $1 maintenance offset charge?" they are just trying to gouge you because you are all fired up that the rental you wanted was available. I would take Caskbill's original advice. Run, don't walk, away. Point rentals are based on trust, and the renter controls the reservation throughout the proces, so I sure would not rent from anyone who had given me cause not to trust.
Or...you could have hooked up with a newbie renter who just doesn't know what they are doing. Everybody has a learning curve, and they may be in the middle of theirs.
Just to be clear on maintenance, it ranges between $3.83 per point and $4.87 per point - depending on where the renter owns their points, not where you stay. From that it's clear that an extra charge of $1 per point is just an extra charge - it's nowhere near the actual maintenance cost.
If you haven't already done so, go back to the Rent/Trade board and read the FAQ and "A Word to the Wise," so that you understand the mechanics of the rental process.
