so if i purchase from a wolesaler i got to pay for the product first
what are the differences between dropshippers, wholesalers, liquidators, manufactuers
Here is the major difference between all you have listed, but having giving you the difference, be aware that each avenue has it's own benefits and draw backs.
Drop Shippers allow you to advertise a product for sale without purchasing it first, giving you an option of starting with low cash flow.
Wholesalers are the link between manufacturers and retailers, buying wholesale products usually involves buying products in bulk quantities to make the most of volume discounts, but this does require cash flow.
Manufactures actually make the product, then they have a distribution process set in place to get their products onto the market, wholesalers being one of their options.
Liquidators are companies selling stock from a range of avenues. Liquidated stock can include old stock, slow moving stock, customer returns, stock from businesses that have gone into receivership and so on. Liquidation is just the process of selling different types of stock, but is usually the cheapest way to buy so long as you can purchase in bulk quantity.
The bigger the load, the bigger the saving is a usual gauge with liquidated stock.
As I said, they are only the general differences between each format, but each have their pitfalls, and you need to seriously research which one is going to suit your requirements best.
I would suggest that you consider all the factors, not just consider factors that your initial budget may limit you too. Ignoring facts about a certain selling platform because you can't afford that option may just cause you bigger drama with the option you end up choosing based on budget constraints alone.
If you are looking at selling on sites such as ebay, I would suggest trawling through threads on this forum to learn from member's personal experience, because it is not the easy road to money that so many seem to think it is!