Need schooling - decisions to be made

A part of my business includes adding corporate logos to T-shirts for a franchise company. I currently stock plastisol in appropriate colors, works great I can do 1 or 100 with no problems.

I occasionally am asked if I can add a phone number or other information to the stock logo... well I need about 4 dozen before that makes any sense... so I don't do that as much as I would like to.

I keep looking at DTG and can't yet see the payback... don't know how well I like the results either.

So how to do low volume runs without big setup costs? I've been thinking about a vinyl cutter, which would also open some other options, for example with my embroidery side.

So I've been trying to imagine how exactly that would work... have to add a cut-out to an existing transfer... what with tape or something? Don't want to try to press twice... will it make sense with 40 or 50 in a run?

So do you think I should be looking at cutters or at something else? I know someone has some good experience and will welcome any advice.

Thanks!