Air Conditioning - Could I have regrets?

My neighbor asked me to install her a new unit being the one she has now is like 20 years old, she wants both inside and outside changed out.
My questions is should I do the job for her or ask her to hire some one else, she's a real good neighbor as it stands now.
I told her I would have to do it on a weekend due to my reg. job.

It can be difficult working for family and friends. You need to lay the costs out clearly and discuss the way the job will progress. Also discuss the future warranty repairs that may arise and how they will be handled. The possibility of losing a friend is always possible if you are not prepared to go the extra mile. I'm assuming that you are able to purchase the equipment and have the refrigerant certification to make the job legal. If not, rule it out right from the start.

Ken

Yes I'm able to purchase equipment and have my EPA certification , I was just wondering what some of you thought of the idea.
She wants me to do the install because she feels that she can trust me to do her a good job and give her a fair price.

Just be sure to be fair to yourself too. As long as you are her neighbor, you will be on the hook. I replaced the picture tube in a TV for my wife's grandmother about 25 years ago. I thought the picture looked good but I ended up buying her a new TV to keep from being a schmuck. Learning from someone elses mistakes is like getting a partial scholarship to the School of Hard Knocks. Good luck either way.

Ken

What worries me some is that what I think is a cool home might not be cool to her.
She could ask me why her unit doesn't bring the temp down to 52 degrees when the temp outside is 98 degrees.
She is really good person, she is a school teacher who is a single parent of twins.

I think Ken pretty much said it all.

Kinda had a "bad" experince w/ my parents.. They built a new house last year, and they got all the kitchen stuff from me. All went well but the counter top. :-( Honestly, it wasn't my mistake.. The color she order was on backorder, and on top of that.. the c-top company made a wrong cut, and again backorder on the island.. needless to say, she was making a few phone calls to me.. :-( I felt sooo bad.. but it was not my doing or my control.. Later on when everythign was done, she did say she was sorry.. She was just tired out and stressed out.. After that, almost thought it be best let somone else do it..

A few years ago I was a computer builder, my sister asked me to build her a top end pc, I said sure, now this was her first pc, she knew nothing about them, I built it and set it up for her, she began surfing the net, finding so-called friends on the net, she received a few virus's , she had an anit-virus program but would never update it, anyway she blamed me for her pc going down, I could not make her understand that it wasn't a hardware issue but a software issue, anyway it went back and forth until finally I told her I had enough and not to ask me anything about the pc that I put together for her which she did leave me alone about it because she knew I was getting ready to clock her lol.
You know thinking back on it makes me second guess myself about installing my neighbor's unit.

As Ken said, be sure to be fair to yourself also. I learned a long time ago, if you work cheap you have all kinds of "friends" but as soon as your pricing comes in line with the market you don't hear from most of these people again.
Something else to be concerned about is insurance & permits, if req'd by local authorities. My honest advise? If not licened & insured, steer clear. It could come back to bite you in the butt.