Not if you are doing fba 

​True - I wasn't looking at it from an fba perspective.

A couple of things not mentioned or that need highlighted. 

20-30% return is very reasonable to expect. So you will need to spend around 200-300 to make 60k a year.

If you are making this a full time job talk to an accountant or financial planner. LLC vs S-Corp are little things that can save a boatload on taxes if done right.

Also if going to be full time business, have you looked into doing builds for birthday parties and other events? Look around there are plenty of mom and pop lego stores that do build events and parties and others that are mobile. Pocketing $200-$300 for a few hours of your time, adds up and you can use those proceeds to grow the other parts of your business

Just thoughts

 Many of you are missing the part where the OP is selling loose parts with 90% of what he buys - all the talk of flipping and long-term holds doesn't fit his current (and I assume future) business model.

For our Belgian poster - I don't have any familiarity of the laws in Belgium, but in the U.S., where the OP is located, it is perfectly legal to sell currently available sets, if he WERE a flipper.

The parts selling model is different than the retired-sets or current-sets-flipping models. If I'm wrong and the OP plans to drift more over to those models, carry on. If not, it's more useful to post what you know of parts selling (if anything).

 Many of you are missing the part where the OP is selling loose parts with 90% of what he buys - all the talk of flipping and long-term holds doesn't fit his current (and I assume future) business model.

For our Belgian poster - I don't have any familiarity of the laws in Belgium, but in the U.S., where the OP is located, it is perfectly legal to sell currently available sets, if he WERE a flipper.

The parts selling model is different than the retired-sets or current-sets-flipping models. If I'm wrong and the OP plans to drift more over to those models, carry on. If not, it's more useful to post what you know of parts selling (if anything).

​This may be my Robitussin induced mind talking, but how is it ok that cost of goods be excluded from his calculation ?  I can see year 1 if he just has millions of bricks to sell from his collection.  Assuming at the end of the year he sells 75% of inventory to reach $60k profit, how is he going to replenish the inventory for year 2,3, etc to make this sustainable ?  Shouldn't that cost be included in the calculation ? What am I missing ?

​This may be my Robitussin induced mind talking, but how is it ok that cost of goods be excluded from his calculation ?  I can see year 1 if he just has millions of bricks to sell from his collection.  Assuming at the end of the year he sells 75% of inventory to reach $60k profit, how is he going to replenish the inventory for year 2,3, etc to make this sustainable ?  Shouldn't that cost be included in the calculation ? What am I missing ?

​He did mention cost of goods sold in a subsequent post (or, replacement inventory as I think he put it).

But I wasn't defending his calculations specifically, I was just trying to draw the attention of the mob to the fact that he's selling parts, which is a different business model, a different sell-through rate, etc. than flipping sets or holding sets.

Thank you everyone for the replies and input. 

justafrog is right, I did mention replacement inventory in my calculation. After reading the posts again I thinking maybe I didn't clarify enough that what I plan on doing is part outs. I do plan on selling some sets, but mostly polly bags and smaller easier to ship sets I get good deals on, like the cement trucks I got for $3.50. In an ideal world I'd do 100% of my business on Bricklink just to A) simplify things and B)save about 7% in fees

I was able to get some down time today and put together some more calculations broken down into more detail. I added further expenses like gas, car mx, and similar expenses. I think my initial goals of $130k in sales to bring home $60k might have been a little low, so I'll continue to run estimate numbers and try to get a more dialed in number on estimated expenses like shipping and office costs. 

I also know I need to establish a baseline inventory. My current inventory is just over 42,200 pieces at just over $6,800, which is a starting point. Using these numbers I'm roughly estimating if I can maintain about 350k items, that would be just over $50k in inventory as a baseline in addition with continuing to replenish more than I sell, which will in turn also help me grow. I am sure I will have better baseline numbers as I increase in size, sales will increase, so when sales become constant at that point I should get a better baseline number. 

Hopefully I explained that the way it was in my head so other can understand it.