The colour of money.

I'll explain the situation:

For the last twelve or so weeks, and for the next six and a half, I've had a Summer Job at a local warehouse. The job, in a nutshell, involves lifting boxes and putting them down somewhere else.

I'm the only person in the warehouse (including the offices) who knows what he's really doing with computers. Sure, there's the company IT Guy, but he doesn't know the difference between his keyboard and the server. I'm often asked to nip up to the warehouse reception to sort out the printer and label printing software. Some people also ask me to help them with little things on their laptops. I'm perfectly happy to do both of these things, as it's what I enjoy doing, and more often than not it gets me out of lifting wellies(come on - 25kg a box!).

A couple of weeks ago, someone who works in the offices needed something doing in Excel, asked the Warehouse Manager (who I'm good friends with) if he knew anyone who could help, and I was asked to do it. Why not? All he wanted me to do was find a way to change the colours of dates in relation to the current date, and tro give him the option to view the dates of a certain colour. Simple. Bit of conditional formatting for the first, and a tiny bit of VBA code for the second.

Then he asked if I could make it so that when he viewed the dates by colour, they showed up in order with the latest first. Again, simple. An extra word or two in the code and it was done.

Then he wanted the same done to other fields. Things get busy at work, so I end up having to do bits of it at home. Fine.

He keeps on asking me to do more things. "Oh, I don't suppose it's possible to make this happen, is it?". "I need to be able to do this... ". The latest thing is for him to be able to Autofilter one field, and then be able to view the dates by colour for the results. Needless to say, things have started to get complicated. Work was dead today, so I spent four hours this afternoon programming. I've also had to spend a number of my evenings working on it - I only get a few hours to myself these days, what with finishing at five and needing to get to sleep early so I can survive the next day.

The point I'm making here is that I'm starting to feel like I'm being taken advantage of. Small, simple things is fine, like conditional formatting, but when the solution requires a few hundred lines of code per single object, well, am I adding small features to an Excel spreadsheet or am I actually building the man a damned program? I've got my own things I want to do, yet can't because he needs the spreadsheet for day-to-day work.

I'm going to get the latest thing finished tonight, and if he asks me to do more, I'm going to ask him to pay me, simple as. The question is, how much do I charge? It's a single Excel spreadsheet, but it's one that's integral to the company. Yet it's turning into a program, with buttons and lines of code behind each button.

A pound for every line of code, rounded to the nearest hundred? A single lump sum (in which case, is it a tenner, or a few hundred?), or something like a tenner for every hour I spend on it?

I don't want to come across as grabbing, but I don't want to offer myself to him for a measly sum that wouldn't even buy me a USB pen, and would leave me open to future exploitation at the same low price.