var payload = await client.SendAsync(request).ReadAs<PayloadModel>();

HttpExtensions.cs

using log4net;
using System;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using System.Web;

namespace CyberBar.BaseAPI.Util
{
    public static class HttpExtensions
    {
        private static readonly ILog log = LogManager.GetLogger(typeof(HttpException));

        public static async Task<T> ReadAs<T>(this Task<HttpResponseMessage> responseTask)
        {
            var response = await responseTask;

            if (!response.IsSuccessStatusCode)
            {
                var content = await response.Content.ReadAsStringAsync();

                var req = await response.RequestMessage.Content.ReadAsStringAsync();
                log.Warn(response.RequestMessage.RequestUri);
                log.Warn(req);
                log.Warn(response.StatusCode);
                log.Warn(content);

                if (response.StatusCode == HttpStatusCode.Conflict)
                {
                    Console.WriteLine("[http] send error - Conflict");
                    throw new HttpRequestValidationException("Missing Id on cloud");
                }

                Exception exception = null;
                try
                {
                    exception = content.FromJson<Exception>();
                } catch {
                    exception = new Exception(content);
                }

                Console.WriteLine("[http] send error - {0}", exception.Message);
                throw exception;
            }

            var contentString = await response.Content.ReadAsStringAsync();

            Console.WriteLine("[http] {0} - {1} - {2}", response.RequestMessage.Method, response.RequestMessage.RequestUri.AbsoluteUri, contentString);

            return contentString.FromJson<T>();
        }
    }
}