Presenting your book to an agent, publisher, or even self-publishing it without at least a basic edit is a bad idea. The typos, questionable punctuation, and possible gawky sentence structure will hit the readers in their faces. They will not be impressed. You may find these ideas to avoid it useful.

Find a part-time job

Maybe you already have more than one job and you still need them for your life. Maybe you are studying. Maybe you have to stay at home with kids, or relatives in need. In that case, this option might be too exhausting for you.
But if you have the opportunity to take one more job for a short time and work hard on your publishing dream this way, do not hesitate.

Sell the things you don’t use

Do you have a new shirt that practically never left your drawer in the last two years? Or is there a fully functional radio you no longer use? Publishing your book is a great opportunity to clean your household and get rid of good things that somehow waste time with you.

Stay away from unnecessary treats

Coffee, sweets… how about finally getting rid of your nicotine addiction? These may seem like tiny pebbles in the sea of editor rates. But they count. You can also plan ahead your shopping and try to save some money.

Present it as a gift for you

You have written a book. You should be proud. Do not hide it and speak about your achievement. You can inform your family and close friends that you do not wish to receive Christmas or birthday gifts. Instead, they can donate a sum of money for your editing.

Polish your manuscript yourself

You should comb and trim your text as much as possible before you actually start looking for an editor. The less work for the editor, the lower the price. Trust your spellchecker. Consult Grammarly. You can also ask your critique partners or beta readers to help you. If you are having trouble finding some, read the recommendations here.
You can also ask the editor to edit just a small part of your manuscript first, point out your biggest problems and give you some advice on polishing your manuscript more before they continue with editing. Many editors are also willing to create a paying plan for the customers. Do not be shy and ask what the options are.

And why should you bother? Writing your manuscript was not easy as well, right? Giving up your chocolate and getting up much earlier/coming back home much later for some time is just another step in your author journey. By denying yourself a little comfort and gifts, you show your author dedication and tough hide. You are doing this for your art. Thus, for yourself. Because you are willing to sacrifice a little to gain something else.