[FClef]

Always best to go with what was there, however that may be cost prohibitive with what was done in the home. There are a great deal of direct vent gas fired wall furnaces with blowers included. They come in all shapes and sizes. Certainly you can find one that will fit your needs. One disadvantage of the wall furnaces is they can tend to be a bit loud. One advantage is that they can have individual wall mounted thermostats. I guess it comes down to what you want to spend and what will get the job done.

 

[FClef]

The problem with re-establishing the new boiler and baseboard radiators is that the main level radiators were removed and I would need to purchase new ones.

Can anyone tell me about the efficiency differences between a natural gas wall furnace and heating with hot water radiators? My budget is about $4000 for everything and I will need to purchase two furnaces. I have a quote to run the natural gas line to all of the levels for $300.

The difference is simple, one is basically a space heater and one is a central heating unit. Efficiency depends on how new your boiler is so comparisons may be difficult. Are the pipes still there for the old radiators?

If the pipes are there you could figure out how much copperfin baseboard each room would need to heat it. If you don't want to do that you can look into some of these architectural salvage places, they may have cast iron baseboard or radiators.