For the sake of a breakeven analysis how much should I expect to spend on a system for 2 trucks?
upfront and/or monthly budget?
I think I'll leave this question to the software experts.
Perhaps you could ask another question: Would the money saved in operating efficiency of a two truck company be enough to overcome the cost of the software, computers, and the training to use them? Probably not; making software an unnecessary (but cool) purchase.
In other words, it may be cheaper to use paper until your company grows. 
Would it be cheaper? thats the idea of performing the cost analysis. Run the numbers. Determine the real ROI, not just the up front cost. As an ex computer guru I know how technology can be used to improve the bottom line of any business.
The shop I work at runs about 500 calls a month w/ 5 trucks. The yard is constantly full, about 30-40 cars.
they use paper and I have observed its a full time position just to handle it.
I plan to take at least 50% of their non- AAA and 30% of their rotation and a 30% from the other operator here.
That means I would have to have another employee or I would have to do it myself. The less time I have to spend in the office the better.
If I am going to borrow 250k you can be sure I am going to have the best plan possible. I am going to carefully consider every aspect. I stack the deck in my favor whenever possible.
Your right, it's worth checking out. Perhaps one of the software reps could pipe-in with some real numbers.
What's your background in computers? I own a computer based company as well.
well....I started out running a small novell network w/ 3 dos pc's on it. I managed the system for 7 yrs, when I left they had offices in SF, SJ and LV, LAN'd WAN'd, running their own exchange server and web hosting and lotsa stuff before that inculding MS mail servers at each location that dialed up and sync'd over the internet lol. I did everything from cabling, web design and graphics.
I had my own consulting biz doin cabling, pc, macs, networks, routers and servers from start to finish. Including a really cool system for Firestone.
Worked at wine.com doin support for about 400 pcs and 40 servers, some oracle and a bunch of other stuff that was pretty cool. and lastly a consulting job, MS platinum provider, navision gold provider.
So I know networking, pc's, macs, nix, email, web server and anything internet related, some php, ecommerce stuff like Interchange and oscommerce, Citrix blah blah blah, bored yet?
I was in my old glory for a minute there.....
Hey! Your a geek like me! 
lol, yeah but people are more willing to pay to get their car fixed than their PC.
Isn't that the truth! If you can buy a new Dell 2400 for $395, it makes no sense to pay me $60 an hour to fix your box. That's why our computer sales are limited to high-end gaming/multimedia boxes where there's still a profitable market. We no longer work on Windows 98 machines either since they are obviously old, low performance, and easily replaced for cheap.
I must say we have spent a lot of time lately cleaning spyware and viruses from computers; mostly corporate where it's financially feasible to do so.
Geez.. guess I'm off topic, sorry.