Ok, I thought you want to sell it as a set.
If you want to sell the unit I would recommend to sell them on the internet so you can reach more potential buyers. You can also sell the lot locally, Craigslist is free, and a lot of collectors look at the ads on Craiglist.
Keep in mind if you sell the unit to a resell shop, the price will decrease 20-30% from market value.
You can sell the item on Etsy, it's like you put the item in a online shop. You may also check Amazon Market Place. Both places have good reputation, and you can easily sell the items for a good price.
If you want to sell the set separately, the value will be 1,000-1,600 for the 1925 American Flyer set and around 100-150$ for the trolley. The trolley is a Schieble Tin-Trams Rapid transit trolley pressed steel hillclimber, painted in blue and red. The other pieces value will be 50-100$
Let me know if I can help you any further, otherwise, please, remember to rate my answer!