The MQL5 Market is MetaQuotes' store for Expert Advisors and indicators, reached from inside MetaTrader 5 or from the MQL5 website. It handles payment, licensing and updates, and it is where the majority of commercial EAs are sold.
Buying and renting
A purchase grants a licence tied to your MQL5 account, with a fixed number of activations, commonly five to ten, each of which binds the product to one computer. Moving to a new VPS uses an activation; running out means buying again. Rentals grant the same licence for a period, monthly to yearly, at a lower price, and expire. Both are non-refundable. The developer can update the product, and updates are installed through the platform.
Demo versions
Every product can be downloaded as a demo that runs only in the strategy tester, so a backtest can be run before buying. It cannot trade on a live or demo account, which means the tester is the only trial available, with all the limitations on the backtest pages. There is no way to forward-test a Market EA without buying or renting it.
Reviews
Reviews come from buyers, are written mostly in the first weeks after purchase, and reflect the experience of installing and watching a rising curve rather than the experience of a drawdown. Developers respond to reviews publicly, and the tone of those responses, and whether the developer offers new settings after every bad month, is often more informative than the reviews themselves. Products with many five-star reviews and a short history are the survivorship page in miniature.
The signals link
Many Market listings link to an MQL5 signal showing the product running live. That is the useful part of the listing, and it should be read with the signal-page guidance: real or demo, equity not growth, deposits, stops, holding times, start date.
A buyer rents an EA for a month, runs it on a demo account at their broker, watches it through a losing week and a recovery, checks that every trade carried a stop, and compares the trades with the developer's signal. The rental cost a fraction of the purchase price and answered the questions a tester backtest could not. The buyer then purchases, keeping the activation count in mind for the VPS.
Use the Market's structure in your favour. Rent before buying where a rental is offered. Read the signal before the reviews. Note the activation count and plan the VPS around it. Expect no refund. And treat the store's popularity ranking as a measure of marketing, not of results.