Cheapest scan tool?- Alarm and TC issues,

[cb77]

Hi all,
I have a couple problems I'm working through on my boxster, I have a 98 2.5:

1) central locking, the key fob never worked so I just used the key in the door, now nothing works. I get a double beep if I try to manually lock and the passenger door doesn't lock with it, switch on dashboard is dead, I assume it is going to be the unit under the seat but I'd like to scan it first just to see.

2) Start the car in the morning and you have the TC and abs lights on, If I drive it up to temperature and restart they will go off and both work perfectly, some days it needs a 5 minute drive for them to go off, some it needs a 30 minute. But they never come on or off while driving, I could get them off and drive all day and it is fine. If I then leave it a couple hours and go back to it they will be back on. Checked sensors using multimeter, was told throttle body could be a problem, cleaned all that out, same with MAF. Sort of stumped now.

So I'm asking if anyone has any ideas on either of these problems and what the cheapest or easiest way just to get some codes out of it is.
Also if it is the box under the seat for the alarm how does replacing it go? Do I need to buy a new one and have it programmed, are used ones not programmable. (May be a silly question but I know a guy breaking one so thought could be cheaper that way)

Thanks