I just wonder that if I got too many jobs which I can not handle at the same time, can I transfer some of them to my friend? if so, should I notify the client? of course I will make sure the finally output have the same quality
Is it moral and professional? No!
Do people do this (including large companies)? Yes.
I can't say I never done it without client's knowledge, but each time I get into trouble as I have to act as a middle man and cannot connect client and my friend directly.
So after few such experiences, I started hiring people for project-wide contract. I pay them salary or percentage and I can easily tell client that a colleague from my office will take care the project as I cannot put enough work hours in it. This way they communicate using our company's tools and I act merely as a project manager and lead developer.
When you tell the client about this, you should be ready to lose this client. Most of them will insist that you do the project since they talked to you, but you have to tell them that you cannot and only your office colleague can. I usually lose 2-3 out of 10 clients working this way.
The concept of morality in business is questionable. And what's ethical is simply to offer the quality services you were paid for and respect your clients. Everything in between is part of a strategy.
I think the main problem is the word FREELANCER. It implies that you work alone at all time while in fact the words BUSINESS or COMPANY are the ones that should be used when you refer to your services. Already by not sticking to freelance, you probably realize that you already know the answer to your question. No one questions the morality or ethic of a business that hires employees; the manager is the one who takes the responsibility for what's going on inside the company and how the work is managed.
So your real concern shouldn't be about morality but liability.
I don't know your age and experience, maybe these advice don't apply to you and your friend.
Should you tell your client?
It's up to you. But I think you should for the simple fact that even though you want to work with your friend and will supervise his/her work, you can't control 100% what that friend will post online, share with other friends, and all the tiny mistakes that could happen. You can't control if that friend will communicate one day directly with the client or some close to the client. You don't know if that friend will always be your friend.
So for these reasons, you should simply mention to your client that you will share the workload with your new team/colleague/partner and will supervise everything. Don't use the word friend, that's very immature and unprofessional (and scary for a client.)
There's ways to say this and be clear that you are still in full control of the quality of the project. Clients are rarely resistant to this, what they want is a guarantee of quality and get the service they paid for on time. They might asked to be reassured but in the end if they trust your judgement and you can deliver the services, you won't have issue with this. It's exactly the same as giving the design work to a designer and you being the one coding the website OR paying an editor to write the content.
Should you transfer some work to your friend?
That's where I think your real issue could come from.
Be aware that doing business with friends and family can be tricky. As PeterMV mentioned, you'll be the middle man and friendship mixed with money can lead to delicate situations. You need to make sure it's clear between you and your friend that you're doing business and the client will come first, the same way as if you hired a stranger. It's usually easy to say when there's no issues but when problems arise, that's when the friendship will be tested. Some friends or family members will expect you to put your client as #2 for multiple reasons and by using various clichés that don't belong to the business world (eg. family first, bff, etc.) For some people, it's hard to accept that while they work for you, you are the client and the boss. Not to mention that if your friend disappoints you with the quality of his/her work, it might be hard for you to deal with this; even worse if you decide one day that person isn't a good fit to work with you. All this depends a lot on your personality and the personality of your friend (and ego.)
The other problem is that being too friendly with "employees" will lead you to reveal a lot of private information about your clients, share files, access, etc. Friends can also get very "comfortable" too, sometimes they do not respect your clients as much as you do. If things ever go bad between you and your friend, you could get caught in uncomfortable situations. And even if it doesn't go bad, it could happen. Only you know how professional and mature is your friend. For example, imagine your friend stored passwords and login access of your clients in a negligent way, and these information get shared; when you work with other people, you need to make sure they use exactly the same methods as you do and the same discipline.
Even if you work with a friend, you should also have him/her sign a NDA. If there's any question or resistance about this,or anything such as "but I'm your friend, you don't trust me?" then don't work with that person. Make it clear that when you work with that person, there's a time for fun and there's a time for business.
As PeterMV suggests, it's often better to simply hire a stranger and keep your leadership role in all this, without mixing it with too much friendship. If you work with a friend, make sure everything is clear and require the same things you would if you hired a stranger.
Just for reference, identifying and expressing intent could be something as simple as this blurb:
- Assignment of Project JOHN DOE DBA ACME SOFTWARE, INC. reserves the right to assign subcontractors to this project to insure the right fit for the job as well as on-time completion. JOHN DOE DBA ACME SOFTWAREP, INC. will be solely responsible for all contributions, management and conduct of any subcontractor(s).
If you are charging per the hour (or day) clearly you can’t pass the job onto someone else without the client’s agreement, as they are paying what they consider your time to be worth.
If the job is on a fixed price, then the question come down to if the outcome will be 100% the same then if you had done it yourself. For example a graphic designer should not pass on design work without the client’s express agreement, but could get someone else to drive to the printer’s to pick up the samples.
If I pay a bricklayer to build me a garden wall, I expect him/she to lay all the bricks as that effects how the wall looks. I don’t care if someone else is employed to move the bricks. The mixing of the mortar is harder to decide, as it does not take great skill, but must be done with the correct amount to give the strength and colour that is required. However if the bricklayer ever claims that it is not his/her fault that someone is not done right, as they got their labour to do it, they are off the job, very likely without getting paid!
It depends on several factors, not least is the contract that you have with your client. If you don't have a contract, probably the client is under the impression that they have hired YOU specifically.
If the contract expressly names you as the worker, even if you have a company, then you are essentially breaking the contract.
If your contract is with your company, and indicates that work might be done by subcontractors or other workers, then you are within the contract to transfer the work (but professionalism requires that you at least notify the client, supply contact information, etc).
In practice, transferring the work, particularly without notifying the client often results in a pissed-off client at best and a lawsuit at worst.
Friends often aren't as committed to the client and the quality of work, and you might find that you are still on the hook for the final deliverables after the friend bails.
Even if things go well, why would the client come back to you?