Anyone wanting to get objective opinions/advice for this sort of situation should get pictures to show both the air compressor and the sandblaster.
A typical home shop 2 cylinder single-stage compressor (in very good working condition) can only support a pressure feed sand wand/gun tip orifice of about 1/8".. even then, there will likely need to be numerous pauses for the compressor to catch up.
Sandblasting uses a lot of electrical energy for the work performed.. it's much more cost effective to use paint strippers, wire brush, acid or scraping methods to remove the majority of paint, rust or other contamination, then use sandblasting only for deep pitted rust. Some commercial corrosion prevention paints are surprisingly resistant to sandblasting.
The concentration of the amount of abrasive in the air stream is a significant factor when it comes to efficiency.. a mixer valve on a pressure feed sandblaster needs to be adjusted when blasting media types or air pressures are changed.