Look at using a DispatchGroup to perform multiple async requests and wait for them all to complete.

For each task you call group.enter() and in its completion handler when you know that request has finished you call group.leave(). Then there is a notify method which will wait for all requests to call leave to tell you that they have all finished.

I have created an example in a Playground (which will fail with errors because of the URL's used)

import UIKit
import PlaygroundSupport

let serviceLinks = [
    "https://example.com/?api/service1",
    "https://example.com/?api/service2",
    "https://example.com/?api/service3",
    "https://example.com/?api/service4",
    "https://example.com/?api/service5"
]

// utility as I've not got alamofire setup
func get(to urlString: String, completion: @escaping (Data?, URLResponse?, Error?) -> Void) {
    let url = URL(string: urlString)!
    let session = URLSession.shared
    let task = session.dataTask(with: url) { data, response, error in
        completion(data, response, error)
    }
    task.resume()
}

let group = DispatchGroup()

for link in serviceLinks {
    group.enter() // add an item to the list 
    get(to: link) { data, response, error in
        // handle the response, process data, assign to property
        print(data, response, error)
        group.leave() // tell the group your finished with this one
    }
}

group.notify(queue: .main) {
    //all requests are done, data should be set
    print("all done")
}

PlaygroundPage.current.needsIndefiniteExecution = true

You probably won't be able to just loop through the URL's like I have though because the handling of each service is probably different. You'll need to tweak it based on your needs.

There is alot more information about DispatchGroups available online such as this article