If you are considering, or have the requirement for larger-scale propagating or seed sowing, why not consider constructing your own propagating bench by using soil warming cables. Soil Warming cables come in various lengths and are an excellent way of raising propagation area temperatures. GrowMad have put together a comprehensive list for you right here. We've listed all the suppliers alphabetically on the left, with our recommendations to the right.
Check them out - Grow On, You'd be Mad not to!