So you'll spend $1k on say 4 figures and if you're in the US you'll be looking at shipping between $20-35 depending on which figure. Now include double boxing supplies because no one wants them shipped in the brown shipper. Don't forget packing supplies and your time spent at the office supply store because their prices are cheapest and oh don't forget about the cranky post office guy who re-weighs your box and makes you spend another $1.75 on postage because your weight was off by 1 lb.
That needs to be done 4 times to make $100 in your scenario.
Most of these figures are not investments now and if the OP to the selling was serious and thinks this is a good idea he's in for a very rude awakening and you shouldn't be encouraging him to lose money.
you don't really get it do you?
when you have a profit margin of 10% it's the 10% of your total cost to sell an item, not 10% of the figure cost.
for example:
Figure Cost inc shipping to you $200
Packing Cost (Box/Bubblewraps/Scrap papers) $5
Postage cost $35 (if your final weight is around the border of a price jump just assume the higher cost you can always refund extras if you want to)
Petrol to the post office $5
Pay pal + ebay fee approx 15% of total price
You can also include inflation cost if you bought the item long time ago but make it simple we don't include it here.
The total cost for you to sell a figure would be ($200+$5+$35+$5) X 1.15= $281.75
Also 15% is an example, what determines your margin is
1.The market price of the item
2.The availability of the item in the market, more = lower price, less = higher price
3.How well the item can sell
4.your running cost e.g warehouse rentals, utilities cost, labors if you hire workers
5.how greedy you are.
sometimes you make a lost via a sales but you gain from other sales, that is business, but if you know how to choose your stocks you have higher chance of making a profit, you can say the same for Stock exchange and Forex however there's alot more unknown variables in those market and it's heavily affected by other players who know nothing about the market that many times it just doesn't make sense.
Toys/Arts have less variables.
I'm not sure if there are other things that can easily yield such profit. Real Estate cost & risk is too high, Limited Edition Sneakers & other fashion stuffs might yield similar gains but i'm not familiar with those things. Video Games usually yield a lost unless you buy low in 2nd hand market & resell high. Same goes for cars unless you talk about classics. There are many other low risk or near risk free investments however they yield way less than 7%.
So you have a 15% margin that is around $42 which isn't bad if you are selling many items.
Like i said if you are just selling 3-4 figures a year it's too much effort for you to make a few hundred bucks.