Just ignore my PM reply. I didn't see this post before I got your PM.
I am not a trapdoor expert but checking the bore and operation of the locking mechanism and trigger pull/hammer fall would be prudent. Look for pitting and corrosion both in the barrel and inside the mechanism as this is a black powder rifle and must be kept clean to prevent rust. If you can take off the stock it might be helpful to find rust/corrosion. Also, it is important for value retention that the stock be original, unsanded with crisp clear cartouches. If the stock has been touched in any way then value should be less.
My 34th Edition of the Blue Book from 2013 shows approximately 232,000 made between 1885-1890. So yours is a late model. It should have 2 barrel bands which appears as correct. It shows value as the following:
100%=$2250, 98%=$1850, 95%=$1450, 90%=$975, 80%=$725, 70%=$625, 60%=$525
Carbine values are considerably more. From the photos it does not appear to be a carbine.
I hope this helps you make an informed decision.
You can call if you need more help.