Simplicity Edge Fire Bowl 40" x15" 6" lip Walnut Acid, fire wood

Can I modify the fire bowl from wood burning to natural gas or LP later?

This is a great question, and YES it is possible to convert wood burning to both natural gas or LP. LP is a bit more complicated since Propane requires holes near the bottom for ventilation.
 
We had a customer that ordered a wood-burning fire bowl and SIX years later came to his senses 😉 and decided to convert and upgrade it to natural gas. 
He had to install the valve next to the fire bowl and took some measurements of the area where the plate with the burner would be, we were able to meet him when we were at the area to get him the burner, and a cover. 
Sometimes, it's a good idea to ask for the bowl with a hole for a valve in case you would want to convert it later.  
Remember, the point of having a fire bowl is to enjoy real heat, without too much work.

Can I select this fire bowl in different color or sizes?

Of course, you can select any color and any finish for the fire bowl.  We are happy to help you choosing that.