Market Evaluation for Home Services Businesses

The story in home services seems to be that demand is not the challenge or pain point. It's said so consistently that I'm inclined to take it at face value, but I'd still like to dig a little deeper into market evaluation. I've come across a methodology for estimating a market's TAM ($300-$600 * Number of Households), but I haven't come across a more detailed way of thinking about the existing players in the market and how much of that TAM is truly up for grabs.

Let's say that a particular market has a few sizable companies in it that are clearly oriented for scale and growth. Maybe they have a dozen plus trucks, they're in multiple markets, and they possibly offer more than one service/trade. Has anyone come across a way to estimate how much of the TAM a company like this controls?

Thinking out loud - you could start with a revenue per truck assumption, estimate the number of trucks at these larger companies, and then multiply the two together to ballpark a particular company's share of the TAM.

Thanks in advance for any and all thoughts on this. Much appreciated!