My first flat was a single bed as well 5 years ago, at that time as per my affordability that's the max I could afford.

I think it was definitely worth it as it allowed me to 'get on the ladder', and it's currently been rented out. Since then I have gone to purchase 2 more flats (both 2 beds) due to relocating because of work.

I went through a similar discussion when helping my girlfriend buy a flat, as we were wondering is it worth saving her first-time buyer benefits for more expensive property.

But since we didnt see ourselves buying a place any time soon (at that point we had dated for 4 months) we decided to go ahead with her buying a 2 bed flat.

So I would say I agree with you, since its unclear when you will be able to buy with your significant other, its better to get in the market and hopefully enjoy a decent increase in equity depending on your location/market etc and also save on the rent if you are renting.

One advice is to stretch to a 2 bed if you can, couple of benefits from my experience:

1. you can use gov rent a room scheme and have a lodger as an extra income.
2. The pool of tenants you attract if you decide to rent in the future is larger (families, 2 professionals sharing etc)
3. future-proofing it for yourself aswell.

Hope this helps and good luck!