Renting or buying?

It occurred to me the other day that in some ways it's possible to compare self publishing versus traditional publishing with buying or renting a house.  Let me explain what I mean.
 
When you rent a house you pay a monthly price for it.  The house is not yours.  Often as a tenant you're allowed to decorate and alter the house to some extent to get it to be how you want.  But often you're not able to; part of the contract says that you can only do certain things with the house and much of it must be left alone. 
 
I think that being published in the traditional way is similar.  You provide the work i.e. your novel and the publisher keeps it up for you.  That is to say the publisher negotiates with you a fee for your work and will then provide a cover for your book, edit, promote and distribute it etc.  Of course as hte author you expect to be kept in the loop at all times regarding your work.  But in the same way that a house you rent is not yours, similarly although the story you've written is your own (as is the money you give to your landlord) a lot of things to do with actually getting the book out there have to be negotiated and may not always prove satisfactory to you.
 
Self publishing can I think be compared to buying a house.  The work you've produced remains entirely yours.  You have to spend the money, time and effort to get it to the point at which you feel it can be shared with the world via Amazon or whoever.  But you are a free agent; you don't have to answer to anyone except perhaps your audience/critics who may not like what you've produced.  Admittedly self publishing is nothing compared to taking on a mortgage!  However, as with maintaining a house, the onus is on the author to make sure their work reads well, that the spelling and grammar are correct and that the cover of the novel is appealing.  One of the most important aspects of self publishing is that the author must rigorously promote their work, a little like forking out for that mortgage payment each month.

I am planning to self publish my novel and I'm currently editing it.   I'm very aware that I need to make sure it reads as well as possible, with no grammar, punctuation or spelling mistakes.  Some people have suggested I hire a proofreader.  Personally I feel at the moment that's too expensive an option for me and I may not see a return on that sort of investment, but I do feel it is very important when you're self publishing to ensure that your work is of the highest standard possible.

Of course there are many benefits to being published by a bona fide publisher.  There can be nothing like seeing your novel in print and holding the final published book in your hand.  But there are certainly many advantages to self publishing and perhaps in the future it will enable authors to have a better deal when it comes to negotiating with a publishing house. 

As always it would be great to hear your views.