Send the developed film to a lab and don't think about bothering them with
the rolls from a Holga. Ask them to make prints on a machine to keep costs
down.

Moda

Your problem is common for a lot of us who like to use their old medium
formats for fun and not for profit. I've just started sending my things in
at Sam's club and payinf about 1/3 of what the local pro lab charges. They
usually ship small prints, but the good shots can be enlarged later. The
knowledgeable folks at your local wal-mart probably haven't even heard of
120 film, but if you put it in the envelope, it does get done. Also, the
more rolls they get, the better they will serve us. The local Sam's said it
was only a $500 investment to allow him to handle 120, but the management
said they would have to make the investment in all their stores. Is that
bad?
Dean

They do sell a 'Holga' enlarger, but it is pricey and it may work
too well to do a Holga negative (in)justice.

You may want to bid on ebay for a $10 Federal enlarger - just the
thing to go with a Holga.

Consider making contact prints at first.  I've put contact prints from my
Holga in my journal as is. Kind of artsy and fun.  Just put a strip of
unexposed but developed developed 35mm neg in your enlarger and get going.

There are also a lot of very inexpensive used enlargers on the market, so
you might be able to get a suitable enlarger for very little.  My first
enlarger was actually a gift from someone with too little room to store it.

PSsquare

 ...but my enlarger will only accept 35mm film.

 Is that your only excuse? Used medium format enlargers abound.  Dan