...started to over heat, smoke? coming out of the front grill and cutting out, filled it up with water and oil, then it worked for a bit, this morning after sitting all night with water in it i drove okay for about 45mins then the needle went in to the red over heating again, any suggestions to what it is? And costings?
Private sale, so bought as seen unless, so we can't take it back..

first thing id replace would be the thermostat .. if it over heats fast good bet that is the problem as for cost about 20 buck if you do it... for a shop price call any shop

Don't even bother trying to find out. Take it back !

Sounds like a thermostat - if thats the problem, your in luck they are fairly cheap and easy to replace.

Also could the fans not be working?
You should hear them running.

lastly check that the hoses are not flattening out when it is started.