Here are some questions to consider:
1.Fully automatic furance(automated program) or a semi-automatic furance(valves controlled by a person in front of furnace)?
2. Max.working temperature,dwell time and estimated time a max.temperature.
3.What atmosphere is needed and which gases are required?
4.If vacuum is required,what is the vacuum level?
5.Size/Volume of the hot zone / usable space of the furnace?
6.Temperature uniformity-Which temperature is required?
7.Heating process details with max.heat up rate and desired cool down rate?
8.Sample name,material chemical composition,size,volume,weight,better to have pictures of samples.Total load of the furnace