void AddOrUpdateTenant(RBaseContext context, int leaseID, string tenantEmail)
{
var ls = context.Leases.SingleOrDefault(l => l.LeaseID == leaseID);
var ten = ls.Tenants.SingleOrDefault(t => t.Email == tenantEmail);
if (ten == null)
{
ls.Tenants.Add(context.Tenants.Single(t => t.Email == tenantEmail));
}
}
