Can I use tourist visas for multiple entries to Thailand within a few months?

METV is my vote. So long as your last entry is done within 6 months of the day they issue the visa.

I think you will be fine taking the 60 day visa exemption each time. Technically there’s no limit but, as always, it’s still at the discretion of the immigration official.

You may want to check your tax status, if you are likely to be in Thailand more than 180 days.

You can do all of that travel on visa exempt entries. No need for any visa.

I’m assuming you’re coming from a country that allows visa exempt entries rather than having to buy an actual tourist visa, but as you don’t state your passport country it’s just a guess.

Your plans of entering Thailand shouldn’t cause any issues. You are doing what a typical tourist could do. Generally immigration are on the lookout for back to back entries on either visa exempt of tourist visas that could indicate that you are potentially abusing the entry system or potentially working here.

That said it’s up to an individual immigration officer to assess your entry so no one can accurately predict what they’d think at the time you give your passport to them.

That's ok as long as you haven't spent most of the last 12 months doing similar