When I bought the 220D (and paid way too much for it -- wish I'd had this forum then!), the dealer asked me if I wanted to trade my POS Buick in on it.
I laughed -- I figured that a difficult to start rough idleing diesel wasn't the best car to use as my only transportation.
That said, I understand the attraction of an MB even with limited resources -- they CAN be very reliable and relatively repair free when in good condition.
I also got my 300D for a good price since the PO bought it on eBay and got screwed -- car was NOT as represented and he couldn't get out of it once he paid the deposit in Florida.
I suppose one could call my 280 SE a "money pit" also -- nothing truely insurmountable, but there is an endless list of things that need to be done eventually.
A friend of mine got rid of his when he spent $5000 on it in less than a year -- subframe mounts, injectors, brakes, water pump (for some reason he was always replacing water pumps on MBs), rebuilt transmission, etc.
Go gently, we all make decisions we regret....
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!